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22z84f | what is the burden of proof? | I recently watch God is not dead and bunch of people were saying that the MC claim can be discredited by the burden of prof and I have no idea what is that........
P.S: English not my native language | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22z84f/eli5what_is_the_burden_of_proof/ | {
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"The \"burden of proof\" is a term that basically tries to assert which side of an argument has the job of convincing the other side and changing their mind. For example, legally (in the US) the person convicted of the crime is innocent until proven guilty. So that means the default view is that the person is innocent and it is the *burden* of prosecution to *prove* that they are actually guilty and change the minds of the jury.\n\nIn debates about things like religion it is much less clear cut who the burden of proof really lays on and kind of depends on context, but IMO it's on the person who is making a claim. If you are arguing that god created people, then it is your job to prove that. If I am arguing that people evolved from other apes via natural selection, then I have to prove it to convince you. It's not clear cut in that case, and in my experience most people just use it as an excuse to not have to make an argument, especially if they don't know what they're talking about. I'll ask for a piece of evidence and they'll just reply \"well I don't have to because the burden of proof is on you, so nah.\""
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241kke | why do dogs let cats take their bed, when they are so much bigger/stronger? | I mean, I thought cats were supposed to be afraid of dogs. Why does that seem to be reversed when they are both in the same house? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/241kke/eli5_why_do_dogs_let_cats_take_their_bed_when/ | {
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"Most animals, dogs especially so, are very situaltionally-aware. Ever been clawed by a cat? Ever had a dog bark at you only to back away when you approached?\n\nSome humans are afraid of spiders that are much smaller than them.",
"Cats are still more \"feral\". A lot of dogs are so deeply adapted to the life with humans and the lack of need to hunt/kill that even a little creature can scare them."
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3u0unl | why do some websites make you add to cart to see discounted price? | Whenever something is on sale, some websites tell you check cart for price. What the point of this and why do they do it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3u0unl/eli5_why_do_some_websites_make_you_add_to_cart_to/ | {
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"This is a quirk in their contracts with manufacturers.\n\nManufacturers aren't allowed to dictate prices (in the US), but they are allowed to set minimum advertised prices. Retailers who wish to sell for lower prices have interpreted this as meaning they can't just post a lower price (which would be advertising), but once a customer has started an order process, they're allowed to tell you, as an individual customer, what the price is.\n\nI haven't heard of anyone challenging this, and doubt any manufacturer would want the expense of bringing this to court to see if this strategy is consistent with their contracts and the legal limits on what manufacturers can do."
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4q2z4k | algae blooms throughout south florida lakes. | I saw a news article on a friend's Facebook feed about a massive algae spike in Lake Okeechobie in FL and it being a direct result of sugar production. Can someone ELI5 why the sugar production is causing toxic algae and what (if anything) the state is doing to combat the spread? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4q2z4k/eli5_algae_blooms_throughout_south_florida_lakes/ | {
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"An algae bloom occurs when the water has too many nutrients in it. A common man-made cause is the run-off from fertilizer into waterways next to farms. The algae covers the surface of the water, blocking out light and reducing the oxygen content, which starves many of the other organisms. It's a serious disruption to the balance of the ecosystem. Algae can also secrete chemicals that temporarily make the water undrinkable or hazardous to swim in.",
"The runoff from any farm, in this case sugar farms adds additional nutrients to the water which provide the ideal growing conditions for the algae and they then grow very rapidly until they cover the surface of the water. For more information on the problem of eutrophication or hypertrophication - _URL_0_"
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3jp9hu | why do they always show the needle going into the skin in movies? | I know they aren't actually being injected with a real needle but why do they show the 'injection' like 99% of the time? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jp9hu/eli5_why_do_they_always_show_the_needle_going/ | {
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"Because it is an easy to do, not \"gore\" and can be a powerful thing. \n\nThey do it because most people have very strong reactions to it. ",
"The SAW movie where the chick fell into the vat of needles. They didn't use real needles, and I assume they would use the same process for other scenes with them.\n\nThey used syringes with fiber optic \"needles\", and super glued them to her skin. Apparently it pulls the skin in the same exact way as a needle would when it's removed. Still, to this day, the only scene in any movie I've seen as an adult that will make me nope the fuck out of a room."
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400pp1 | why do some films, like waterworld, become classic films that everyone remembers even though they failed at the box office and were seen as not very good when they came out? | And then some films that did well and were seen as much better, like Leon, are just not as remembered and referenced as much in pop culture. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/400pp1/eli5_why_do_some_films_like_waterworld_become/ | {
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"Sometimes failure is just worth remembering.\n\nWhen things are so bad it's spectacular, it's usually worth talking about for one reason or another",
"Waterworld was at the time the most expensive movie ever made (topped two years later by Titanic). With the expense came the hype. You had leads with Kevin Costner hot off 'The Bodyguard' and 'JFK' plus Dennis Hopper who was hot from... well, it's Dennis Hopper!\n\nThe star power, the expense, the hype, combined with an otherwise forgettable movie is what made it stand out in the memory of critics and general audience. \n\n'Ishtar', ten years prior, had suffered a similar fate, costing over $50million to make, with much of the money going to Dustin Hoffman and Warren Beatty. Again, the star power, the expense, and the shooting in Africa, combined with the painfully dull story made 'Ishtar' a laughing stock for a very long time, until, well, 'Waterworld' was made.\n\n'Leon' turned a profit in the theaters, was generally well liked, and became a cult hit after Natalie Portman and Gary Oldman hit their groove. It is a pleasure to watch over and over."
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5ky5hh | why do music videos before 2011 look so blurry, even though there were hd cameras available? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ky5hh/eli5_why_do_music_videos_before_2011_look_so/ | {
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"If you're taking about what you see online, it's probably because uploading HD wasn't really a thing back then. They uploaded them and they were compressed and at lower quality. "
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3ox0m3 | what is esperanto as an "artificial language"? if you speak the language what is the reason you're learning it and how would you persuade other people to do so? | Hello, I've come across with this peculiar language called Esperanto on Duolingo. I've searched it on google and it says it is an "aritificial language", which is my first time ever hearing this phrase. How does it work? Who speaks it? Would there be a reason to even speak this language when you don't know when it would be useful? If you're an Esperanto speaker please elaborate what this language is and how it works! and especially why you're learning it, maybe you could persuade me to learn it on Duolingo :) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ox0m3/eli5_what_is_esperanto_as_an_artificial_language/ | {
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"Various Esperanto speakers wrote their reasons for learning Esperanto in [the thread \"Why learn?\"](_URL_0_) at /r/esperanto.",
"Esperanto was intentionally constructed to be easy to learn and meant to be a \"universal\" neutral language. Its creator wanted it to be an official second or third language so everyone had a shared language to speak to each other in (something of a pipe dream, granted, but you can't fault the guy's ambition). Most languages evolve naturally over time rather than being put together on purpose. While artificially assembling a language has the advantage of removing some of the stupid rules and hard pronunciations of a more natural language like English, few people are encouraged to learn it until many other people have already learned it and started using it. \n\nI personally don't know Esperanto. According to Wikipedia about 2,000,000 people worldwide can speak Esperanto fluently.",
"RE: \"Artificial language\"\n\nA natural language is one that develops because people speak it over time, like most of the languages you know.\n\nArtificial languages are ones that, at some point in time, someone made up. Probably the three most famous ones I can think of are Esperanto, Klingon, and Elvish.",
"Ever have one of those moments when you learn about something in the English language and you just sit there dumbfounded and declare \"English is really dumb\"? \n\nEsperanto was designed to not have those moments, because linguists created it from scratch. Words and grammar in Esperanto haven't evolved over time; they were chosen to be logically consistent and clear. You don't have to worry about there/their/they're all sounding the same and you don't have to get to the end of the sentence \"I read this wonderful red book about reeds yesterday\" to know how to pronounce the second word.\n\nOn the other hand, you can only talk to people who learned Esperanto, so there's that problem ([relevant xkcd](_URL_0_), albeit for Lojban instead of Esperanto, but they're the same general idea)."
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3idytd | how do news outlets like vice news ensure their journalists survive when doing documentaries like the islamic state? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3idytd/eli5_how_do_news_outlets_like_vice_news_ensure/ | {
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"ISIS, despite their reputation, are neither stupid (mostly) nor aimless. This is true for most terrorist groups if not all.\n\nNews agencies cannot guarantee their journalists survival but they can negotiate with them in order to allow its journalists to do a documentary about them. This deal is likely to have a bunch of conditions attached and even then, there's small chance of this agreement being ignored.\n\nThis is one method. The other method is to film undercover.\n\n",
"They don't always survive \n\nMany journalists died reporting and filming both the Vietnam and Iraq wars",
"Here's the story from the ISIS reporter in particular.\n\n_URL_0_",
"No ones safety is guaranteed, it's a journalists will. Also terror groups like ISIS like the fear that they can spread with news agencies. ",
"Well there are no guarantees of safety. ISIS is particularly PR savvy—it did more for them to show him around and not kill him than to behead him like the others. IIRC that documentary was filmed and produced before ISIS began their beheading campaign. I can't imagine any legitimate news organization risking a reporter's life to go embed with them at this point.\n\nOn a similar note, it's also important to point out that many news organizations rely on stringers or freelancers for their overseas coverage, particularly in the Middle East. It's cheaper for them to do that and sadly it often means the reporters aren't as well paid/have less job security and don't always have access to the resources a big news organization can offer if they find themselves in a pickle. \n\nThe war correspondents I've met over the years tended to be adrenaline junkies... it's an extremely dangerous line of work for them, but that's what they're into doing. ",
"It's not just who you know, it's who do you know that know other people. \n\nJournalism, and not the punditry we've grown accustom to through major news outlets, is about finding these people and learning their stories. People like ISIS, Syrian Rebels, minors in Chile, etc... want their story told, but they know there are risks in telling their story and they may be reluctant to trust a journalist who might \"misrepresent\" them.\n\nSometimes the channels required to arrange these kinds of documentaries/interviews/exposees require a lot of \"I know a guy, who knows a guy, who knows a guy whose brother could get you a meeting with [group name here]\" conversations where the sources are putting themselves in danger (either with their group, or enemy groups) for the simple act of arranging a meeting. Sometimes the people actually going into the field have formed a friendship with the people they're interviewing after months of talking; a single friend in a war torn region can literally save your life when you're talking to people that behead journalists for propaganda purposes. Many times these journalists are putting a lot of trust in their sources. They might get out of the airport, get in a cab and stay at a safe house for a few weeks while the organization debates what to do with them. \n\nUltimately they're able do these documentaries because the group they're filming has already given them freedom to do so long before the filming takes place. There is a lot of risk and when we hear stories of journalists getting beheaded, it can sometimes be because they got into the wrong taxi on their way to meet a source that would have arranged them an interview with the very group that kills them-a large group like ISIS doesn't know every member of its organization so saying \"bob can speak for you\" means fuck all when a different cell hasn't even heard of a bob. \n\nFor groups that don't rely on external displays, like a drug cartels, rebels and such, reporters are usually given a background check long before they come close to anybody in person, and the group will simply drop contact if they don't like/trust the reporter. \n\nThis is where the idea of \"journalistic integrity\" comes in. The right to free press, in the US and other places, includes a protection of these sources, but not every outlet will protect their sources (too much anonymity can discredit a story after all), sometimes a news outlet will gain a reputation for misrepresenting a source and not be trusted by some groups. For an outlet like Vice, they're able to get the stories they do because A: people watch vice (remember, they want their story to be told), and B: Vice's has a reputation for not misrepresenting their sources, giving them more weight and scoring them more high profile documentaries. \n\nIn short: these groups want their story to be told, journalist will seek out members of these groups through various channels (sometimes easy, sometimes very hard and sometimes not fully legal (but the journalists may be protected depending on their country)). The documentaries might be impassive but behind the camera these journalists are usually on friendly terms with people who want us to understand them better.\n\nBecause even a group like ISIS is full of a individuals who see themselves as something more than a political affiliation. And if anybody want's to do an interview with a terrorist group/militant group/white supremacist organization etc, etc... they better be prepared to talk to them as people first and party members second. \n\nI hope that made sense. ",
"Vice doesn't have to ensure anything, because the journalists aren't employees, they're freelancers.",
"They aren't guaranteed safety, and some journalists have actually been kidnapped and/or killed on the jobs. For example:\n\n_URL_0_",
"I've had the opportunity to listen to Vice producers give interviews. The question about their safety is always brought up. \n\nThe ELI5 version goes like this:\n\nYou want to go to neighborhood X, because it has a really great pizza place. But neighborhood X isn't safe. In fact, it's pretty bad. \n\nOne day, you're talking about the pizza place and someone says, \"I live right there. I know the neighborhood well. When I go, you'll come with me.\"\n\nWhen you go with this person, he knows everyone around and people assume you're \"cool\" and belong in the neighborhood. No one hassles you. If they do, your new friend will intervene. \n\nThis guy bringing you to the pizza place is called a \"fixer.\" He knows the area and most of the big shots. He can get you in with little trouble. And most importantly, he can get you out alive. \n\nTV shows like Vice, No Reservations (now, Parts Unknown) use this same approach to ensure \"safer\" travel. The fixers are locals with strong roots in the area. "
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b2bj2h | how can meteorologists tell us what the weather will be like in 50-1000 years when they can’t even accurately tell us what the weather will be like tomorrow? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b2bj2h/eli5_how_can_meteorologists_tell_us_what_the/ | {
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"Weather and climate are different. This requires a certain amount of words. Sentences. Stuff like that. \n\nIt's not the same, and so your question can't be answered appropriately. ",
"If you’re referring to climate change predictions, climate and weather mean different things. Climate is a broad, overall weather pattern, whereas weather is a moment to moment change. Meteorologists can accurately predict weather a few hours to a day in advance within a margin of error (thing 30% chance of rain vs 70% chance, they’ll never say 100% chance but they can get pretty close) and they can also see overall climate patterns worldwide (like the record high temperatures progressively getting higher)."
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7dxhva | how does internet time synchronization work? | Basically, how can you accurately, to the millisecond, synchronize your time to a server somewhere? Isn't there a time delay when communicating through the internet?
I've read posts like [this one](_URL_0_) and [this one](_URL_1_), but they never really covered *how* the synchronization works. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7dxhva/eli5_how_does_internet_time_synchronization_work/ | {
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"You should look up the NTP page on time exchange. It describes what you're looking for in very easy to understand language (even simpler than the Wikipedia page).\n\nNTP lets you calculate the *time difference* between you and the server. It relies on one of you- in this case, the server- having an accurate reference time.\n\nWhen you send a request to a time server, you tag on the time sent *as you see it* (t0). When the server receives your request, it tags on the time received *as it sees it* (t1), then sends a reply with the time the reply was sent *as it sees it* (t2), and finally, you get the reply with your time *as you see it* (t3).\n\nA simple example. Let's say your clock says 13:30 (t0), but the actual time is 14:00 (which the server knows correctly). You send a request to the server. It takes 1 minute to arrive at the server, so the server notes that it received your request at 14:01 (t1). It takes a minute to think, sending you a response at 14:02 (t2), and it arrives- according to your clock- at 13:33 (t3).\n\nWhat's the time difference between your two clocks? Take t1 - t0: that's the time difference between you and the server, plus travel time in 1 direction. This works out to 31 minutes.\n\nNow take t2 - t3: That's the time difference between you and the server, **minus** the travel time in one direction. This works out to 29 minutes.\n\nAdd the two times and divide by two, to cancel out the effect of travel time. This gives you 30 minutes- your clock is behind by exactly that amount. So you adjust your clock ahead by half an hour, and you're back to proper time.\n\nDo this over a long period of time, averaging out your results, and looking for strange outliers (remember that traffic on the Internet is unreliable), and you eventually get confident enough to say \"alright, this is the current time\"."
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c2nahh | how does calcium strengthen our bones? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c2nahh/eli5_how_does_calcium_strengthen_our_bones/ | {
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"Calcium in our bones is actually a composition which is very hard. Without it, bones resemble something like the cartilage in your nose. The best ELI5 I can give is for you to test it yourself:\n\n- buy chicken wings with bones.\n- eat\n- dunk bones in vinegar overnight or so.\n- acids dissolve the calcium, and the bone is no longer rugged.\n- bend the bone like a rubber band :)\n\nContrary:\n- safely hold the bones over a hot flame (eg. stove).\n- flame burns cartilage-like stuff.\n- break bone with absolutely zero effort :)\n\nThe lesson here: bone strength is not only due to calcium, the strength comes through flexibility also. Otherwise, they would be very brittle, like a crayon.\n\nTry the above, let me know your findings :)\n\nEdit: thousand edits, non-native speaking mobile user+autocorrect"
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9nu5pf | how are polyester fibers made? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nu5pf/eli5_how_are_polyester_fibers_made/ | {
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" \n\nPolyester is made up of long chains of polymers. Today the two major kinds of materials produced are Polyethylene terephthalate (PET) and poly-1, 4-cyclohexylene dimethylene (PCDT). PET is used on a wider range as it stronger than PCDT. However, in terms of elasticity and resilience, PCDT has more consumer uses.\n\nThese pellets or chips are synthesized from petroleum-based products. The process of synthesis is carried out using a chemical reaction which involves coal, petroleum, air, and water. These resins are made up of purified terephthalic acid (PTS) or dimethyl terephthalate (DMT)\n\nThe most common type of chemical reaction used to make these plastic materials occur at very high temperatures in vacuum. Usually, a petroleum by-product (alcohol) and carboxyl acids are mixed to produce a compound monomer or “ester” This reaction process is known as polymerization.\n\nThe polymer material created in the process of polymerization is further extruded into long fibers that are stretched for some time (Approximately 5 minutes) to gain original length."
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exk103 | why do people talk backwards sometimes? swapping the first letters of a two word phrase or name. ex: brain damage= dain bramage. butterfly= flutterby | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/exk103/eli5_why_do_people_talk_backwards_sometimes/ | {
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"Pobody’s nerfect.\n\nIt’s just a common joke. Never heard these specific examples, but it’s either a.) a stroke reference or b.) in the case of my example, a joke that the user can’t even get that phrase right. In your case, I’m gonna go with Option A, especially considering the brain damage one.",
"If it is intentional, it is called a spoonerism. \nIt's a simple kind of joke that's been around forever but seems more popular lately.",
"When it is not intentional it is a type of Literal Paraphasia. There are several types of paraphasias but this type of letter switching can be one. It can happen to a normal healthy person on rare occasions just like word dropping, meaning we cannot think of the next word of a sentence and it is 'just on the tip of the tongue'. But if it occurs frequently it can be the symptom of a neurological problem like a stroke or turmor, or induced by brain trauma."
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48rkoe | how do places such as churches, hospitals, shopping malls etc. become abandoned? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/48rkoe/eli5_how_do_places_such_as_churches_hospitals/ | {
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"Churches become abandoned when the flock leaves. Maybe they found a new church to go to and no one wanted to buy the old one, so the owner (usually the ministry at large) just locks it up and leaves it.\n\nHospitals become abandoned for largely the same reason, they find a new hospital and just lock up the old one. Often with equipment still inside.\n\nMalls are different, they are often abandoned before they finish construction due to a lack of funds.\n\nAs to why they don't get demolished? Because no one has the time or money to bother destroying it when it's cheaper and easier to just board it up, put a fence around it and say no trespassing. ",
"I submit for your approval the story of the [Mall of the Great Plains.](_URL_0_)",
"I lived near a nearly empty mall once. A guy who still had one of the few remaining stores told me that the landlord raised the rents too high, so most of the stores left. The landlord figured he'd get new tenants, but the mall was not in a great location and the higher end stores that would pay higher rents weren't interested. Also, big box stores and online shopping were now competing with the kinds of stores that used to be in the mall, so the old stores weren't coming back. I moved from that city years ago, and the last I heard was that the mall was being used for community college classes.",
"Here in Alabama, we have one mall on the verge of closing, largely a result of (1) the opening of a newer, nicer semi-outdoors lifestyle mall a few years back, (2) A movement of the city's white people towards the south-eastern cide of the sity, that ties in with (3) a growing, government housing/decrepit apartment dwelling, largely black/Latino population in the area around the mall, a result of the city (4) moving housing projects away from the main hospital for... reasons?\n\nAll the white soccer moms are scared of \"thugs\" walking in the same direction as them for more than 5 feet, so they keep themselves and their disposable income away. A million tears were shed at Chico's and The Sharper Image. \n\nHow do places become abandoned? Racism, in this case."
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6t6si6 | how does nuclear radiation make metals corrode/become brittle? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6t6si6/eli5_how_does_nuclear_radiation_make_metals/ | {
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"To explain this I need to explain what radiation is. There are 3 types of radiation, Alpha, Beta and Gamma. Alpha radiation is when and unstable nucleus shoots off two neutrons and two protons as one entity, basically shoots off the nucleus of a helium atom. Beta radiation is when it shoots off an electron. Gamma radiation is when it emits gamma rays. In all these cases, the unstable nucleus does this to reduce its own energy to make it more stable. Now we have to look at the atoms of the metal, all of these different types of radiation have different effects on the metal. Most commonly, radiation knocks electrons off the metal atoms otherwise it just eats it up. When an electron gets knocked off, the metal atom turns into an ion. Ions are not stable, and tend to react with whatever is around them. In the case of most metals, this is probably oxygen if it's on the outer layer of the metal. This would answer the corrosion part and some of the brittleness. Another thing that happens is that the alpha radiation hit a metal nucleus and basically gets absorbed into it. Now this metal nucleus has just changed into a different element because of the addition of two protons. Usually this means that the new nucleus becomes very unstable and quickly decays into something else. And basically introduces a bunch of impurities into the metal. This makes it brittle. Another really fringe case, that doesn't happen often is that it courses the metal atom to split (aka. Nuclear fission), but this only happens with very specific atoms under specific conditions so it doesn't happen often. "
]
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[]
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ppidb | the "seven seas" and what a "sea" actually is | What are the "seven seas" mentioned so often in culture, and, furthermore, what is a "sea" defined as, as opposed to any other body of water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ppidb/eli5_the_seven_seas_and_what_a_sea_actually_is/ | {
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"The term 'seven seas' _URL_0_ has referred to differing seas and oceans throughout the centuries and has a lot of cultural variation. Medieval Europeans and Arabs both wrote about the seven seas but they were referring to different groups of bodies of water for example. If you read 'seven seas' in a text you'll need to do a bit of detective work on the context to find out what they're actually referring to if anything specific. In general it just refers to great expanses of water i.e 'we sailed the seven seas' means 'we were sailing for a long time and for a great distance' \n\nThe main difference between an ocean and a sea is just one of scale, oceans are massive and really, really deep. "
]
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"http://en.wikipedia.org/wiki/Seven_Seas"
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1m86tx | how does an electric vaporizer like the ploom pax do to tobacco or cannibis that makes it better for you than smoking it? | I've never been able to smoke tobacco in the past but I've been able to inhale from a Ploom Pax vaporizer. What is happening in this process that makes tobacco and pot easier to smoke through a vaporizer than smoking it straight? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1m86tx/eli5_how_does_an_electric_vaporizer_like_the/ | {
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"Most of what is physically bad for you in marijuana smoke is caused by burning the plant, making smoke in the first place. Micron sized particles in smoke are bad for your lungs. Burning anything also produces very toxic carcinogens like carbon monoxide. In lab studies people have found that the carcinogens start to release at about 375 F. Vaporizing at this temperature avoids the release of most of the harmful toxins associated with inhaling smoke. In a vaporizer you have a heating coil that reaches the temperature you want, then you pull air over the heater, it then passes over the marijuana vaporizing the thc and other active ingredients."
]
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[]
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23tx2s | if we become dissatisfied with the way the internet is run, what stops us from creating a new worldwide computer network? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/23tx2s/eli5_if_we_become_dissatisfied_with_the_way_the/ | {
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"Nothing. You will need some money to run the fiber and buy and maintain the routers. By *some* I mean tens of billions U$D.",
"The Internet isn't \"run\" by anyone. The physical portion of it is provided by a large number of companies world wide. If you're not happy with a particular provider then you would need to create new physical links to bypass them, your ability to actually do that would vary depending where in the world you are.",
"The biggest thing stopping you (or *anyone*) from creating a new computer network is simple: where do you put the wires?\n\nYou can't just start digging up streets and burying them; you have to get permission from your local municipality to do that, and they won't grant it because they already have a deal with whoever your ISP is.\n\nYou can't hang them off telephone poles, because the phone company owns those poles, and they aren't going to lease them to a potential competitor unless they are ordered to by the municipality (who won't do it because they already have a deal).\n\nEven if you could get the permission to dig up the streets and/or string up the cables, then you actually have to go and *do* it. And you have to wire up everyone's houses. And that gets hellaciously expensive very quickly. It's so expensive that not even the biggest ISPs in the US want to do it.",
"Strictly this:\n\nThe internet is a concept based on the interconnection of devices, governed by protocols. No one can own it (short of governmental regulation), people can only participate in facilitating the support of its infrastructure by having servers, routers, and connecting through ISPs to a global network of the same.\n\nWe can't just \"create a new one\". This would literally mean we'd have to create our own ISPs, lay new cable, put out our own satellites, install our own major comms hubs, buy+install+maintain hundreds of thousands of servers... basically do what made \"the internet\" over all these years, in what, a month?\n\nEven if we could do that, we would be essentially creating the same thing. We'd just be creating an \"alternet\", in which all its service providers and end nodes would be operated by different people than those who controlled the previous. And none of that would matter. Because individually, you cannot control the internet. You can only control your contribution to it. The service you provide. And if you pan out a ways, to see the broad scope of individuals providing interconnected services, that is the internet, and the only reason and only way they currently play along, is because money. Plain. Simple. The internet.",
"Nothing is stopping you from doing it. But, there are a few hard problems to overcome.\n\n * The current Internet is incredibly useful: it has a ton of users, services, and infrastructure. A \"new\" Internet would be much less useful, because it has far fewer users, services, and infrastructure. This is called a network effect. [See Metcalfe's law.](_URL_0_)\n\n * If there were a \"new\" Internet, the first thing that people would do is connect it to the old Internet.\n\n * Though there are technical issues with the current Internet, the main dissatisfaction that people have with it is, I believe, the kinds of interference that happens from government intervention, political forces, and the great unwashed ugliness of humanity using it. Because of this, the \"new\" Internet would likely suffer from the same problems as the old Internet as it becomes popular enough to draw the attention of the same forces that try to exploit it."
]
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"http://en.wikipedia.org/wiki/Metcalfe's_law"
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1o98yn | why do some people think shakespeare was a made up person/alter ego? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1o98yn/eli5why_do_some_people_think_shakespeare_was_a/ | {
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"The plays contain detailed knowledge of court manners, foreign locations and references to historical facts as well as familiarity with earlier playwrights.\n\nThe facts known about William Shakespeare suggest he was an actor, not that well educated, did not frequent the social circles where he would pick up that kind of detailed information. \n\nThe dichotomy between the known facts about the man and the sophistication of the works leads to questions whether someone else actually wrote the plays"
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6caw73 | what happens when the safety screen is removed from a microwave (and you use it)? | I've heard it can cause nerve damage but I'm not really sure about the science behind it/what sort of specific damage it can cause, etc. ELI5! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6caw73/eli5_what_happens_when_the_safety_screen_is/ | {
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"So the way microwaves work is by creating standing waves of electromagnetic radiation - light - that cause the water molecules in whatever you're microwaving to wiggle around, generating heat.\n\nIt will do roughly the same thing to the water in your skin. The effect won't be as pronounced, since you can't set up a standing wave (a standing wave is one that doesn't *go* anywhere, it bounces back and forth in the space its in perfectly so the waves line up and constructively interfere to create taller peaks). But it will still wiggle the water around in your skin and heat up your skin, which as you can imagine is not particularly good for you. The good news is that it won't penetrate too deeply into your skin. The bad news is that it doesn't have to: it can really mess up the nerves that sit just under the outer layers of your skin to relay your senses of heat and touch.\n\nAnd it's *really* bad for your eyes, because your eyes are squishy balls of mostly water, and your retinas are very exposed (because they have to be!) and very sensitive. So, you know, don't stare directly at the waveguide of a microwave oven without the protective cover."
]
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tqm6v | lactation | How does the body know to lactate? Where on the nipple does the milk come out of? What triggers the end of lactation?
BONUS: Male sympathetic lactation.
Edit: Thanks, everybody! Y'all have been very helpful. Appreciate the answers. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/tqm6v/eli5_lactation/ | {
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"Ok I'm I know some of this because I was pregnant, basically a boob is made out of milk ducts covered in fat, when a girl is pregnant hormones make the breast start getting ready for lactation, that why during pregnancy breast swell up. After a baby is born something call oxitocyn(I think) is realized and this send signals to the brain to let out what's called the first milk(I don't remember the scientific name) which can be clear or yellowish and only a ill bit of it is realized, this milk is full of antibodies and other nutrients a newborn needs, the more milk a baby drinks the more milk is going to come out of the breasts, it's a supply and demand thing. ",
"Also, a woman doesn't need to be pregnant to give milk, it can be induced with nothing more than (properly measured) daily stimulation of the glands and nipples. It can be sped up with herbal formulas from the store, but they usually aren't necessary. They'll stop making milk when no more is needed. i.e., When the kid/partner stops nursing.",
"I'd still like to hear about male sympathetic lactation!"
]
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6tc45t | why is it that lakes and the ocean seems to calm and be "still like glass" towards and through the night? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6tc45t/eli5_why_is_it_that_lakes_and_the_ocean_seems_to/ | {
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"There is a wind effect. Land will start warming as the sun rises. So the air above it rises. This means a wind toward the land from water. As the sun sets it ceases to heat the land. So this warming land wind effect ends. No wind means it is still.",
"I remember learning about this in 7th grade. It’s pretty complicated to understand, but it has to do with wind. It’s called **Land Breezes** and **Sea Breezes**. It has to do with warming of the sea and vice verse to the land. Land Breezes happen at night and Sea Breezes happen at day! 🌴 🌊 "
]
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1k0o88 | how can one survive a nuclear explosion/atomic bombing? | Imagine you are at the office, doing your everyday things at work when suddenly an atomic bomb is dropped at the center of your city, lets say 10km(6 miles) away from you. Is there any way you can bolster your chances of survival? If yes, what is it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1k0o88/eli5_how_can_one_survive_a_nuclear/ | {
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"I hear jumping into an old refrigerator works pretty well. ",
"There are definitely things you can do, but they don't increase your chances of survival a whole lot. People close to the epicenter will pretty much all die, no matter what they do. If you are a tad further away doing the following might help a bit though.\n\nBasically there are three parts of a nuclear explosion.\n\n1. The heatwave and initial radiation. There's not really much you can do about this. Either you survive or you don't, depending on how close to the epicenter you are.\n\n2. The shockwave. If you had some sort of warning prior to the explosion, close your curtains to minimize the amount of glass splinters, and to lower the amount of fallout that makes it into your house/office and then head towards your basement and hope the shockwave won't tear your house down. If you don't have time to do that just seek cover behind something, a wall, a table, your chair, anything that can potentially stop projectiles heading towards you.\n\n3. The fallout. It will usually ~~take a couple of minutes~~ roughly an hour (but it can vary a lot) from the shockwave passes before the fallout falls down to the ground. In some cases it might be best to seek out medical attention in this time, but otherwise you should go somewhere in the basement with thick walls. You want as much between you and the outside as possible. Make sure to stock up on supplies too since you'll likely have to stay there at least a few days until the initial radiation has decreased enough for it to be safe enough to evacuate. Having a way to stay in contact with the rest of the world is important too. Get a radio with some spare batteries so you can hear the government announcements regarding evacuation and such.\n\nYou can find more information in the old BBC cold war instructional videos they made. It's actually really interesting to watch. They are called protect and survive. You can find them on youtube."
]
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2brxl3 | what is the difference between css and html? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2brxl3/eli5_what_is_the_difference_between_css_and_html/ | {
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"Html is the language that is used to put content on the Web pages. \n\nCSS is what makes it look nice. \n\nCSS can also be used to ensure that all pages on a site (say a corporate site) all look the same by being able to use it's information on all html pages. ",
"HTML is the language used to build a Web page; CSS is used to style the HTML (it's capable of a lot more, but that's not ELI5).",
"HTML is a means of providing structure and meaning to the contents of a web-page. CSS is a means of specifying its layout and visual style.",
"Yes, one is to display, one is to make it look nice, but that doesn't explain it enough. The main purpose of CSS is to separate the two.\n\nIt used to be that you just kind of had HTML. \"Draw a block here. Put a table there.\" To style them you would say \"draw a black block here that's 300 x 200 size. Draw an image that is centered here\". The problem is that you kind of have to do everything individually. To draw another black block you'd have to say \"draw a black block here that's 300 x 200\" each time.\n\nWhen you throw in CSS, you can style things based on attributes. The most commonly used attribute for this is the \"class\". Let's say your big black box is for showing image captions. You can say \"draw a caption box here. Draw a caption box there.\" Then you'd make a CSS sheet that says \"a caption box is black and 200 x 300\".\n\nWhat's the point? Well, after you've drawn all these caption boxes you realize that they don't look right on mobile devices. Now what? Easy! Just go to your CSS and add \"I want captions to be narrower if the viewport is narrow.\" Then all your black boxes will adopt that change without you having to do each one manually.\n\nHe biggest advantage of keeping this separation is that you can make sweeping style changes by changing just one CSS file.\n\nCSS has gotten even cooler with SCSS, which helps you be even more shorthanded about how you style your page. Let's say you want your site to have a blue theme. Chances are you'll have dark blues and light blues. Normally in your CSS you'd have to manually tell it what dark blue looks like, and what light blue looks like. With SCSS you can just say \"Here's what type of blue I want. Dark blue should darken it by this much. Light blue should lighten it by that much.\" Then you can say \"You know what, I think I like purple better.\" You just change the one blue color, and the rest of it follows along.\n\nOne problem with this shorthand is that the browser doesn't know how to read it. It just knows CSS. So you have to turn it into CSS by compiling, which is to run it through a program that can interpret your little SCSS file and spit out a huge CSS file that the browser can read.\n\nTLDR; CSS makes you able to make sweeping style changes without having to manually change each HTML element on your pages. SCSS takes that idea even further by letting you write a shorthand CSS that you can compile into the long, sometimes repetitive CSS your site will use."
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chdpxw | how does anesthesia work during a liver transplant? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/chdpxw/eli5_how_does_anesthesia_work_during_a_liver/ | {
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"Nobody really knows how anaesthetic agents work, including anaesthesiologists. There are a few theories though."
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4ustv7 | why do movie releases decide to use nr (not rated) instead of nc-17? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ustv7/eli5why_do_movie_releases_decide_to_use_nr_not/ | {
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"It is not a choice between the two. NR means they have not been reviewed for rating. It means they have not submitted to the process. NC-17 means that they have submitted to the process and are so raunchy that they are just a few steps shy of a porno. ",
"Movie ratings are actually trademarks of the MPAA - you can't use them without their permission. NR is not. It's easier to not submit a movie and mark it \"Not Rated\" than it is to submit it and get any rating.\n\nNot Rated is not necessarily equivalent to an NC-17 rating (though it's certainly got that implication, and theaters are likely to treat it the same). It's also used for early film trailers (usually phrased as \"this film has not yet been rated\"), and for directors cuts or unrated cuts of films where the original was submitted to the MPAA, but the cut appearing on the disc was not.",
"The rating system is run by a committee that reviews and rates the film's based off of given items including--but not limited to--language, violence, sexual appropriateness, and subject matter. Film ratings have become such a prominent force in the success of a movie that directors and producers often change portions of their films to achieve a more marketable rating. The most successful is PG-13 with NC-17 the least. For that reason, some film makers opt to not have their film rated at all rather than reduce their work for the sake of a better rating. That in of itself is pretty much film suicide as well though. At least for movies looking for a large theatrical release.\n\nIt's, at times, a controversial process. If you get the chance, watch the documentary This Film Is Not Yet Rated (it was on Netflix last I checked) which goes into detail about how the system works, how those in charge are abusing it, and even the sexism that occurs surprisingly often. ",
"What movies are you talking about? I don't know if I have seen an NR not an NC-17 in theaters in ages. If you are talking about home media (Blu-ray, DVD, digital, on-demand), those are usually extended/alternate versions of the theatrical, since they are different from the theatrical release, they cannot use the same rating, so they can either resubmit it for a rating, or just release it as NR. \n \nNR means 'not rated' and is not always a more adult version of the theatrical release, so if there was an alternate version of say, Winnie the Pooh, it could be NR."
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2qwe15 | what determines the flight ceiling of an aircraft? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qwe15/eli5_what_determines_the_flight_ceiling_of_an/ | {
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"Aircraft need air for two things:\n\n1. For the engines to burn - combustion needs fuel and oxygen, if the air is too thin then you can't get enough of the latter. \n2. To provide lift - if the air is too thin for the particular wing design, then you're not going to get enough air flowing around the wing to keep the aircraft flying.\n",
"Engines primarily. As the altitude increase the air density decreases. Above the aircraft's flight ceiling the engines will struggle to get enough oxygen to sustain power. The engine will flame out and the aircraft will stall out (a skilled pilot would glide it back into a lower altitude and possibly be able to re-ignite the engines). \n\nAerodynamics of the wings and control surfaces also play a role. In less dense air the aircraft will have less control and require more lift to stay level. At extreme altitudes an aircraft not designed for that altitude would feel sluggish at the controls. \n\nThe third and less common restriction is a pressurized cockpit/cabin. Without a pressurized cabin or onboard oxygen the ceiling is always at 14,000 feet above sea level. Starting at 10,000 feet the thinner air begins to impact the crews' ability to fly. Army regulations limit the amount of time an aircraft can operate above 10,000 feet without oxygen. Any flight above 14,000 feet requires onboard oxygen. This restriction is due to the crew members and not the aircraft's ability to operate at higher altitudes though.\n\n\n(Source: Former US Army Helicopter Crew Chief, I mention US Army regulations just because those are what I know.)"
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1ptibs | why is the "time remaining" for file transfers on windows always inaccurate? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ptibs/eli5_why_is_the_time_remaining_for_file_transfers/ | {
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"Most of the necessary information isn't available ahead of time, and it would take a significant amount of time to gather. So basically the computer just guesses, and adjusts its guess as it gathers that extra information.",
"From my experience, it depends on the files being transferred.\nIf it is multiple files, Windows may put up an Estimate because each file is initiated separately. It takes time to initiate the transfer, and time to complete the transfer for each individual file. Windows doesn't appear to be accurately able to determine the time basically because of this. It doesn't appear to factor in the additional time it takes to make a copy of each file, and then send it. It also has a lot to do with the medium being used. USB 2.0 has a lower maximum transfer rate than USB 3.0, but it also relies heavily on the Hard Drive reading rate, as well as the processing capabilities of the PC (If you're running a lot of processes, it may lower the priority of a file transfer or vice versa).\n\nSo from my understanding, it's a lot of variables to factor in between the hour it takes to transfer 2GB to a USB Stick.\n\nAs far as the \"5 seconds remaining\" forever, I have no idea. It would take someone more knowledgeable than me to determine that.",
"Had this in my clipboard from last thread so id thought I've share it with you guys too; [related xkcd](_URL_0_)"
]
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d2kqdg | why do cars use different types of fuel? e.g. diesel, unleaded, gasoline etc. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d2kqdg/eli5_why_do_cars_use_different_types_of_fuel_eg/ | {
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"There are two types: Diesel or gasoline (aka petrol in many countries). Both fuels are made from crude oil. Unleaded (gasoline) has different grades of octane ratings: 87, 95 etc. Octane is one of the compounds which make up gasoline. Higher grades provide more combustion pressure so are used in performance engines. \n\nDiesel engines have higher torque, so are more powerful when starting up and at low speed. This is why they are used in trucks, trains, vans etc. Petrol engines can rev higher and so have better performance at high speed. For cars the difference between the two has been narrowed, diesel engines run a lot smoother and petrol engines can produce greater torque than in the past. These days they are both suitable for powering a passenger car. \n\nGoogle first if you don't know how an engine works. And this [article explains why diesels have higher torque](_URL_0_)."
]
} | [] | [] | [
[
"https://www.drivespark.com/off-beat/why-do-diesel-engines-have-a-high-torque-output/articlecontent-pf83981-025084.html"
]
] | ||
1enh4y | why is the obama administration's drone program so controversial? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1enh4y/eli5_why_is_the_obama_administrations_drone/ | {
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"Many reasons.\n\n1) They are acts of war. Only Congress can declare war. So off the bat, his drone program is unconstitutional.\n\n2) They are war crimes. The drones are striking within the limits of foreign sovereign nations. \n\n3) Furthermore, the accuracy of these strikes has been called into question. It is estimated that only [2% of those killed by the strikes are \"high level militants\"](_URL_0_)\n\n4) There have been some very questionable targets. Such as [funerals and mourners.](_URL_3_) And sadly [this is not an isolated incident](_URL_1_) There are even reports of [rescuers being targeted](_URL_4_). If you can imagine a building near you blew up, you might offer to lend a hand without knowing who was in it. You also might get killed for it if you live in the Middle East where the Obama administration was droning. \n\n5) They are counterproductive. By engaging in this drone campaign we may ironically be creating \"terrorists\" at [a faster rate than we can kill them](_URL_2_)\n\n6) There has been question if drones will be used for 24/7 surveillance in America. People argue this would be unconstitutional as a warrant is needed for surveillance beyond simply standing in public areas and looking into someones yard.\n\n\nEDIT: clarification\n\nHope this helps you. ",
"Most arguments are not against the drones themselves, but the controversial killings. The drones are simply a scapegoat."
]
} | [] | [] | [
[
"http://www.guardian.co.uk/world/2012/sep/25/drone-attacks-pakistan-counterproductive-report",
"http://www.salon.com/2012/06/04/obama_again_bombs_mourners/",
"http://www.salon.com/2012/09/05/drone_blowback_is_real/",
"http://www.salon.com/2012/02/05/u_s_drones_targeting_rescuers_and_mourners/",
... | ||
9h1afx | how does lidar work, and how is it able to be so accurate? | I get that LiDAR works like Sonar and Radar, in that it sends out a pulse and measures the time which it takes to return to a sensor. I don't understand how we are able to measure precisely, when the time it takes light to travel the distance seems to be too small to measure. For example, if a person is five feet (1.524m) away from a LiDAR system, it would take about five nanoseconds for the light to travel one way, and about five on the way back. This is ten nanoseconds. Do we have the ability to measure this time with enough precision, and use the speed of light to determine distance? Or is there something else going on? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9h1afx/eli5_how_does_lidar_work_and_how_is_it_able_to_be/ | {
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"Indeed LiDAR can measure time with precision; typical horizontal resolution is about 0.5 to 1m, allowing ± 1-3 nanoseconds imprecision.\n\nIt's not _that_ impressive. The clock in a mundane desktop computer is faster than 1 nanosecond by tick (1 GHz == 1 tick per nanosecond).",
"A 1-gigahertz processor has a cycle run every billionth of a second (1ns). It seems like an insanely-small amount of time to us (and it is), but might be \"normal\" for equipment designed to run at such quickness. A Renishaw XL-80 laser interferometer can provide a linear resolution of 1 nanometer even when what it is measuring (typically a machine) is moving up to 4 m/s, if you could somehow slow time down and had a display that was super ultra fast, you could see it count down nanometer by nanometer while something is coming at you at about running/sprinting speed.\n\nThat said, yes, we do, or at least an estimate. LiDAR used in law enforcement settings probably isn't going to have some insane multi-million dollar clock inside, but the appreciable price tag they carry does include a nice accurate clock. It's pretty much needed to be using light to measure distance, and to be able to pulse at 30ns or so to begin with. There may be some inaccuracies in LiDAR but it is probably not enough to discredit them. The technology is also used in imaging and has been for decades; the Apollo 15 mission used it to map the moon's surface, and an airplane can make a map with a resolution of 30cm or better without having to be low to the ground. As time goes on and technology improves the kind of equipment that can measure a nanosecond or nanometer becomes cheaper and more available.",
"Yes, there is something else going on. The LiDAR typically uses a technique called “optical heterodyne detection”, which allows for more precise time of flight measurements than a given clock speed would otherwise allow. Even with picosecond accuracy (one trillionth of a second!)\n\nImagine you’re at a wave pool. The wave maker starts making a whole bunch of waves. When one of them hits the end of the pool it bounces off the edge and a smaller wave goes back towards the wave maker. When the top of that little guy gets to the wave maker, the wave maker can see it! Since the wave maker has been making all its waves exactly the same size and length, it can compare where it is at in the cycle to the top of that returning wave. Halfway through making another wave? A quarter?\n\nLight moves so fast that in LiDAR applications, whatever distances we’re usually interested in, the light gets back before we’re done making another wave. And since we can figure out how much offset the returning wave is from the one we’re making, that gives us more precise time-of-flight than our clock can even measure."
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1tqgly | how did the science of fractals improve cartography? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tqgly/how_did_the_science_of_fractals_improve/ | {
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"In terms of maps made with computers, it allowed for better DEM's (digital elevation models) that are made from TIN's (triangular irregular networks) by leveraging the mathematics behind fractals. This led to better contours as well as interpolation methods such as kriging. Think of a single triangle that represents a mountain, the more triangles you have that make up the mountain the better representation of the mountain you can have. Tldr improved graphical rendering of complex data"
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1tbbqh | what is the unity engine and why do so many games use it these days? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tbbqh/eli5_what_is_the_unity_engine_and_why_do_so_many/ | {
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"First, what is a game engine in the first place? It's a bunch pre-made things that most games need. So using an existing game engine saves you time when you don't have to make all those things yourself. Instead you can focus more on the creative aspects that are unique to your game.\n\nUnity has grown to be a very comprehensive game engine with options to publish on several platforms: Windows, Apple, iOS, Android. And what's more, it's initially free. Indie developers especially can just download it and start developing instead of having to pay something that would be way too costly for a single hobby indie programmer. If you don't have a proper studio going and you're not even sure if you'll ever finish your game, then free or low cost is really the only practical option.\n\nYou can use the free version to even publish your game royalty free as long as your gross revenue is low enough. But the pro version too is fairly cheap ($1500) if you're convinced that you'll be able to finish and sell your game.",
"Unity 3D game engine, is a general purpose game engine, and it is a rather handy one. You can build very big games like GTA or racing games or small mobile games with it. \n\nPrior to it, most important game engines were very expensive (500 K kind of expensive) but Unity changed the scene with its pricing model, with a free version which is very very capable and a pro version with certain added funcionality. So it gained a very big community that produces and sells assets, helps each other etc. Despite it has poor documentation, you can find an answer to most problems you encounter from forums etc. I think its biggest advantage is this community. Otherwise you can find better game engines in many aspects."
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5jf008 | if heat spreads evenly through liquid, why are there "warm waters" and "cold waters" in the oceans that are all connected? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5jf008/eli5_if_heat_spreads_evenly_through_liquid_why/ | {
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"It does not do so instantaneously. And you have different levels of eat influx at different locations. Then you have the effects of salinity causing very noticeable difference between layers of water. And finally, you have water currents.\n\nThe ocean is not homogenous.",
"Heat doesn't spread \"evenly\" through a liquid. There can be many phenomena that screw with simple diffusion.\r\rEventually it will reach equilibrium if you remove external forces and give it enough time, but the oceans on earth are constantly acted upon.",
"Set up a portable space heater in your room. Turn it on. Notice how warm the air is right by the heater. Now walk away from the heater. The heat spreads through the air, but the air is colder when you're far from the heater. Why? Probably because your carpet heated up, and your walls heated up, and your furniture heated up, and your cat (now sitting by the heater) heated up. The heat was not all just staying in the air.\n\nThe heat in the oceans comes from somewhere, but it can also go somewhere too. The sun shines on the ocean and heats up some of it. Then the heat escapes into the land touching the water. It escapes into the air above the water. It escapes into infrared radiation floating away into space. And yes, it spreads throughout the water.\n\nBy the time the heat would spread to far away water (which takes time), much of that heat has already escaped. "
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eskoy1 | in cities where the tap water is clean enough to drink, how does the water stay clean throughout the whole process to get to the your faucet? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eskoy1/eli5_in_cities_where_the_tap_water_is_clean/ | {
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"Water towers create positive water pressure in the entire system at all time, meaning when there are any cracks or leaks the result is that clean water goes out rather than dirty stuff going in. Since people are always using water the system is always having more clean water go through it. In the circumstances where they have to work on the pipes and contaminants can get in, that's what \"fire hydrants\" are really for. They open them up and let clean water flush anything out, spilling into the street for as long as is necessary to ensure it's clean.",
"The pipes are clean. The pressure in them keeps things out of the pipes as well. You’ll see water companies issue “boil water” notifications if they lose pressure or have a break in the line that could let nasty stuff in. After that, they’ll flush the lines and usually add some chlorine to the water to kill nasty germs.",
"So this quote came from an uncle who was a civil engineer in the 50's and 60's, \"the solution to pollution is dilution.\" In other words, he was saying if enough water is running through the pipes, the crap's not noticeable. Probably not today's best practice.",
"In addition to what's already been mentioned. The water is treated with Chlorine, or Chloramine to kill bacteria, viruses and the like. It takes surprisingly little."
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ajnsqd | how do 2d animators keep characters and elements consistent? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ajnsqd/eli5_how_do_2d_animators_keep_characters_and/ | {
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"If you practice drawing the same thing over and over, eventually you will get better and better at consistency. Just because it's a skill you have not yet mastered doesn't mean it's not a master-able skill— it's just something you have to put more practice into. There are many methods that can help get you closer, too— like breaking objects (and people) down into a series of smaller shapes and keeping their sizes in proportion to each other consistently in ratio, before then applying details like facial features, clothing, etc.",
" > animators - who have to draw thousands of versions\n\nThat's half your answer, practice. The other half is best practices like reference images, or simply as a result of key framing."
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65o1uf | how are these snails floating on the underside of the water? | in this post _URL_0_ the op says his snails are so small the the surface tension allows them to float on it which i kinda get but a more thorough explanation would be cool | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65o1uf/eli5_how_are_these_snails_floating_on_the/ | {
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"These particular pictures look like the snails are working with a mucus layer, so I'd have to be able to see the whole tank to tell you what's happening for sure.\n\nWe'd see this a lot in Beta fish tanks. The Betas (a.k.a. \"fighting fish\") are native to a flood plain that only really floods seaonally. So they \"fight\" for the depressions because most of the tiny divots can not support two fish for the dry season.\n\nThey also produce a thick slime/mucus that floats to the surface of their fist-sized dollop of water. This mucus layer slows evaporation and so increases the chance that their little blob of water will survive until the next rainy season.\n\nThis is why you can keep a beta in a literal cup (eight fluid ounces) of water for months at a time.\n\nThe mucus is quite thick and slimy.\n\nThe snails are very small, so they can stick to that mucus layer and crawl along it quite easily.\n\nNow other fish have similar mutations for similar reasons so in a still water tank you'll get surface scum where various material joins with the water's \"surface tension\" to make a surprisingly strong layer of one composition or another.\n\nIt's not strong compared to your finger, but it's strong compared to the more-or-less neutrally buoyant snail's means of propulsion.\n\nAnd even in clean water with virtually no scum the water's surface tension is pretty strong to start with, and the mucus from the snail's foot is going to let it create the needed thickness.\n\n---\n\nBeneath all this is the question of \"what is surface tension\" in water.\n\nIf you look at an water molecule it's one Oxygen and two Hydrogen atoms. This forms a little \"V\" shape because the Oxygen atom is about eight times larger than the hydrogen. The Oxygen needs to \"borrow\" an electron from each of the Hydrogens so it gets very minus-ee, and the hydrogen's one electron each spends so much of it's time servicing the Oxygen atom's needs that the two hydrogens get very plus-ee.\n\nBasically if you draw that \"V\" shape and put two little pluses, one on top of each horn of the \"V\" and put a big minus under the point at the bottom, you've done a decent job of making a \"charge map\" of the water molecule.\n\nNow the plus-ee parts of any one \"V\" are going to be attracted to the minus-ee parts of another V. This is called the \"hydrogen bond\". So if you made a bunch of these V, like if you printed a bunch of large \"V\"s and cut them out, you could make shapes by lining up the pluses and minuses.\n\nIt turns out that the water molecule shape is slightly wider spread than most Vs in fonts. In particular if you put six together plus-to-minus it would make a circle with six outward-pointing pluses. (This is why snowflakes are six-pointed if they are flat, more minuses stick to the six outward pointed pluses, and so on.\n\nSo in the full thickness of the water the V's are arranged in three dimensions. They are pointed in every conceivable direction.\n\nBut at the surface of the water they don't want to point their pluses up into the air. So at the surface they tend to form a \"mat\" Some of their pluses point down into the water, and the rest are horizontal.\n\nSo the surface of the water is a tightly laced arrangement of pluses stuck to minuses. This interlocked mat of molecules is so strong that it can hold up things. Heavy things like bugs (look up \"water strider\") and sewing needles (a fun science experiment).\n\nWhat's strong from above is strong from below.\n\nSome things, like particular mucuses, can make this barrier extra strong and thick. While other things, like soaps (e.g. \"surfactants\" as in \"surface actors\" but in academic speak) can weaken and break this tension.\n\nSo the snails may be small enough to just use the surface tension...\n\nOr they may be adding to the surface strength with their own snail slime.\n\nOr something else, like a fish or decaying plant matter, may have already added some structural reinforcement to that surface tension.\n\nTL;DR? Scum. Scum is strong. Scum is common. And snails are good at making and using scum.",
"My time to shine!\nI breed these snails and they trap air inside their shells that allows them to float. _URL_0_",
"Snails are honestly super fucking cool. Basically, they trap air in their shells and use that to float around. They can release a little at a time, or do it all at once. Mystery snails in particular are my favorite because they're known for \"parasnailing\". Parasnailing is when they climb something tall within the tank (a plant, decor, or just the glass wall of said tank) and jump off, letting all of the air out of their shells. I had one snail that did basically nothing else with his day - every time I looked over, he was climbing the glass and jumping off. "
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7d8q23 | when global warming reaches the critical threshold of 2c higher on average, is the process irreversible? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7d8q23/eli5_when_global_warming_reaches_the_critical/ | {
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"We know that CO2 is a greenhouse gas - it allows light from the sun in, but traps the infrared light that the Earth emits, thus heating Earth. Thus higher CO2 levels leads to an increase in temperature. \n\nHowever, it is also true that higher temperature leads to higher CO2 levels. A lot of CO2 is absorbed by the oceans, and the oceans' ability to do this is diminished as temperature increases. \n\nSo we get something of a feedback loop - increased CO2 leads to higher temperature, and higher temperature leads to increased CO2. So, if Earth's temperature increases enough, then even if humans decrease CO2 output to zero, the reduced CO2 absorption by the oceans will cause CO2 to keep rising which will cause temperature to keep rising."
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62remm | how do "ones and zeroes" make up *every* bit of digital information without running out of combinations? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/62remm/eli5_how_do_ones_and_zeroes_make_up_every_bit_of/ | {
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"Because we can always add more bits.\nAnd each time we add a single bit. The amount of possible combination double.\nFor example:\nA 3 bit space can store\n000\n001\n010\n011\n100\n101\n110\n111\nThats 8 combinations\nSo lets add one more bit. They could now store\n0000\n0001\n0010\n0011\n0100\n0101\n0110\n0111\n1000\n1001\n1010\n1011\n1100\n1101\n1110\n1111\nSee? Now we can have 16 combinations!"
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5zllr9 | macro vs micro economics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5zllr9/eli5_macro_vs_micro_economics/ | {
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"Microeconomics is the study of how individuals and firms make choices about purchasing and selling goods, and allocating their resources.\n\nMacroeconomics is the study of how nations make choices about monetary and fiscal policy, and allocating the aggregated resources of the nation."
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2xx1cs | how do live twitter feeds on tv get monitored? | In light of TSN's recent accidental broadcast of the offensive Phaneuf-Cuthbert-Lupul tweet, I'm wondering how those networks sort through trash to broadcast specific tweets. Algorithms? A person reading every single one and green-lighting the ones that are okay? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2xx1cs/eli5how_do_live_twitter_feeds_on_tv_get_monitored/ | {
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"I assume hat just like some online video games, there is a profanity/language filter, it twitters doesn't show a tweet contains the word/phrase",
" > A person reading every single one and green-lighting the ones that are okay?\n\nThis. Works pretty much the same way a seven second delay works for audio broadcasts. Probably easier, because you can take your time and greenlight instead of trying to screen everything at once."
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22i5pw | do animals get depressed when they can't find a mate? | Like humans do? I have a non-neutered male cat who doesn't interact with other cats. Will this make him sad or depressed? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22i5pw/eli5_do_animals_get_depressed_when_they_cant_find/ | {
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"This generally depends on the animal. Herd animals, like cows, horses and elephants can get depressed if isolated from other animals like them. As cats tend to be rather solitary, your cat should be fine. The only problem is if you're unable to spend time with your cat. As long as you're able to give your cat a reasonable amount of attention, he should be just fine.",
"I don't know if your cat can be depressed without other cats around, but I have seen a cat get depressed from jealousy. At my friend's ranch they have lots of cats. One day they brought a new female kitten and this male took her under his wing. Played with her, showed her around, helped her get food, these kinds of things. This lasted for a few month, until the female kitten reached sexual maturity. At this point she was \"taken\" by one of the largest, meanest males around, and seemed to completely forget her former friend. It was very sad to watch. The rejected male would keep to himself. He stopped eating. After a few days he was gone, nobody saw him again."
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18b4k3 | carburetors. | How do they work? What is jetting? What/How synch? Idle synch? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/18b4k3/eli5_carburetors/ | {
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"On a very basic level, a carburettor takes fuel and passes it through a very fine nozzle so that it becomes an aerosol. This is exactly the same process as when you depress the nozzle on a can of underarm deodorant, or fly spray.\n\nOnce the fuel has been turned into tiny particles suspended in the air in this way, it becomes much much more explosive, and is therefore ideal for use in an engine.\n\nBy using different size jets and adjusting the precise mixture of fuel and air you can adjust the speed that the engine runs at. So jetting is the process of replacing the jet (usually called a \"needle\" in a carb) with another one which has a slightly different size.\n\nWhile it's interesting to understand how carbs work, very few modern vehicles use them any more, almost every engine built in the last 10-20 years will use direct fuel injection to the piston.",
"The job of the carburettor is to mix the right amount of fuel with the right amount of air.\n\nThe main body of the carburettor is just a chamber that air passes through on the way to the engine. There's a big disk in that chamber called the \"throttle butterfly\", which literally throttles the airflow by blocking it off as much or as little as you require - this is what you are moving when you use your throttle (aka gas pedal).\n\nAt some point on its journey, the air will pass through a narrow gap. For reasons that are beyond ELI5, this causes suction, and this suction is used to suck fuel into the air, through a \"jet\". The more air going into your engine, the more suction, and so the more fuel gets mixed in.\n\nThe exact way that the fuel is measured is more complicated than that. There are two main ways of fine-tuning it - one adjusts the size of the narrow gap, so that the suction is always the same, and then the amount of fuel is judged based on how small the narrow gap has been made. A \"needle\" is moved in or out of the jet to adjust the amount of fuel. The other way of doing it leaves the gap the same - which sounds simpler, but has the disadvantage that it doesn't work well when your engine isn't using very much air, so you have to add extra complexity to get around that problem, usually by having two different points in the airflow where fuel can be added - a main jet, and an idle jet.\n\nAs another reply has said, whichever method is used, it's important that the fuel gets turned into a fine spray when it's added to the air, otherwise it won't explode correctly.\n\nThe other major part of the carburettor is the float chamber. This is the place where it stores its fuel ready for mixing with air. It uses a float, similar to the one in your toilet cistern, to maintain the correct level of fuel, which is crucial if it's going to work correctly.",
"My motorcycle actually has 4 carburetors, one for each cylinders, which brings in a new factor, balancing the carbs. Otherwise you may send more fuel to one cylinder, and in turn killing the performance. "
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etfs0y | how do tranquilizers work? why can't we use tranquilizers on humans? what would happen if we did? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/etfs0y/eli5_how_do_tranquilizers_work_why_cant_we_use/ | {
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"If an animal accidentally dies due to tranquilizer it’s not really a crime if someone dies because you tranquilized them it’s man slaughter. Each persons dosage needed is different due to bodyweight so it will be easy to under or overdosed them. Meaning you can either kill them or do little to nothing most of the time. Also you run the risk of it reacting to drugs or medications they may be on. plus they are temperature sensitive so you have a very small window after you take them out of the case and you only get one shot because the gun shooting it makes the barrel hotter so the subsequent shot will get too hot.",
"There are human tranquilizers. They're used for convulsions, psychosis, and anxiety/insomnia. (We don't really use the term \"tranquilizers\" anymore, though. We classify them more specifically as anticonvulsants, antipsychotics, and sedatives/hypnotics.)\n\nThey work by acting on chemicals in our brains called neurotransmitters.",
"We use tranquilizers on humans all the time.\n\nTranquilizers are used to calm people down, deal with anxiety, sedate them, and to control conditions like psychosis and convulsions.\n\nThe medical field just refers to them by different terms like sedatives\n\nWe just don't actively shoot humans with tranquilizer darts like you see in the movies.",
"It requires pretty specific amounts. Too little it doesn't work, too much they die. The amount is dependent on things like bodyweight and could be affected by medical conditions. There can be allergic reactions to the type of sedative, etc.\n\nIn animals we just use a high dose and keep hitting it with it till it stops. If the wild cougar dies no one is suing the state and no one is responsible for the death of a person. \n\nIts not safe enough as a less than lethal option, and using it as a lethal weapon has legal, moral issues and why not use a bullet anyway."
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3cy5f0 | in a million or so years as our sun cools, could venus go through an earth-like period where it becomes a habitable planet and teeming with life? | Or in a more basic question, will our solar systems habitable zone move as the sun dies? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cy5f0/eli5_in_a_million_or_so_years_as_our_sun_cools/ | {
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"First, it's not millions of years, it's billions - 5.\n\nAnd after 5 billion or so years it'll expand first, really messing up Venus (possibly destroying it outright) before collapsing again.\n\nIt's not likely any life on that may exist on Venus (or earth) will survive through the death of the sun.",
"Well, in a million years the sun should be just fine. However, in a few billion years as our sun starts to enter the red giant phase it will expand and consume large swathes of our solar system (earth included) before it collapses into a white dwarf. During this period of expansion and collapse the habitable zone will be constantly shifting such that life (as we understand it)would be highly unlikely.\n\n_URL_0_\n\nHope this video helps:)"
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8gaf75 | why is it that no matter how hard you try when you wake up, your eyes/face will always look like you've just woke up? | If someone just woke up, you would know. No matter how hard they wash their face, or try hard to pretend like they havent been sleeping. why? what causes us to look that "just woke up" look? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8gaf75/eli5_why_is_it_that_no_matter_how_hard_you_try/ | {
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"I'm not an expert by any means but I believe the primary cause is dehydration throughout the night. When you're dehydrated your skin tends to look more flushed and puffy.\n\nIn addition to this your facial muscles have basically been relaxed for an extended period of time and due to your positioning the fluid that is in your body is redistributed a bit (similar to how ankles will look more swollen if you're on your feet all day)",
"I thought this had to do with melatonin levels, there’s still quite a bit when you wake up. And if you get woken up early and unexpected, those levels are through the ROOF!",
"The correct answer here is the horizontal nature of sleep.\n\nWhen we're awake we're on our feet and a lot of fluid can collect there. If I had to guess 500cc per leg on average. \n\nYou can check this by examining the skin at the border of your socks after a day of standing. There's a ridge at the border of your socks because the tension of the elastic has kept some of the water from distributing entirely there. \n\nWhen you lay horizontal that fluid redistributes. Some gets pissed out. Some ~~good~~ goes to your head and neck. \n\nBoth head and neck are particularly susceptible to minor changes in hydrostatic pressure. Thus, puffy eyes and cheeks, deepened voice, even blurry vision. \n",
"Gravity and your body fluids, when you lie they flow horizontally rather than vertically which cause the puffy look on your face, that's why usually the back of the dead bodies looks swallow and puffy",
"So in zero gravity or microgravity this doesn't happen, you look the same?",
"Becuase you didnt grab a brush and put on a little makeup?"
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8pysoo | why is antialiasing graphically intensive? | Sorry if this is a stupid question, but I don't quite understand. Without AA, the image is generally sharper, with AA, the pixels are smoothed over, so technically it's just a blur... So how the hell is it more intensive than no AA? The only AA I know that isn't intensive is the fortnite, and the DOOM antialiasing. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8pysoo/eli5_why_is_antialiasing_graphically_intensive/ | {
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"I'm no expert and AFAIK there are some different types of AA, but it's not as simple as adding a blur (and either ways, a blur is still an extra filter that you'd be applying over the image, so it would be more intensive than no AA)\n\nThe one kind of AA that I know is that it samples the pixels around the edges of stuff and basically adds extra pixels with appropriate colors in order to smooth out the edge (so in a black outline against a white background, rather than having some black pixels against white pixels, you'd have black pixels and then a few gray pixels and then the white pixels, making a smooth transition).",
" > Without AA, the image is generally sharper, with AA, the pixels are smoothed over, so technically it's just a blur...\n\nIt isn't just a blur for several reasons. First is that it isn't applied to the entire scene as a whole; you aren't trying to blend everything including textures which might have sharp features on them, you are just trying to blend the transitions between polygon edges and more distant backgrounds. Objects within the scene are going to be composed of many polygons themselves so you can't just direct your efforts toward the edges of any polygon either. Figuring out where the aliasing would occur is computationally expensive itself.\n\nSecond it isn't a simple blur being performed. For example you want to blend areas where the polygon edge would be cutting a pixel into a fraction of itself, adjusting the intensity between it and the background an equivalent fractional amount. But in areas where the polygon boundary closely matches the real boundaries of the pixels you don't want your algorithm to be mindlessly blending with surrounding pixels.\n\nSo you see it isn't really a \"simple blur\" at all and heavily references the underlying geometry of the scene. All that takes computation power to perform."
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cqpm7y | when washing your hands with soap, does the soap kill the bacteria? even if the soap doesn’t say antibacterial? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cqpm7y/eli5_when_washing_your_hands_with_soap_does_the/ | {
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"* Mostly what soap does is surround dirt and other particles inside of a slippery bubble.\n* This slippery bubble can then easily be rinsed away.",
"No, soap is a surfactant. So that means one end of the molecule is hydrophobic (repels water) and the other end is hydrophilic (sticks to water). The hydrophobic end sticks to dirt and oil and when you pour water over it, the water sticks to the hydrophilic end and the running water washes away the dirt. . . Antibacterial soaps however do contain chemicals that kill bacteria.",
"Not necessarily. Regular soap simply rinses away dirt and bacteria. It may end up killing the bacteria by doing this, but that is not what makes soap effective. Antibacterial soap should only be used sparingly to avoid creating super bacteria that are resistant to it (Through the process of natural selection)."
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25tdiz | how does commentary work in sports video games? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25tdiz/eli5_how_does_commentary_work_in_sports_video/ | {
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"There is a bunch of pre-recorded phrases for specific situations and as these situations occur the commentary will be played out. There is hours upon hours of commentary for each game and each language. ",
"I can't say for sure, but having some limited experience in game design, I assume it uses a simple form of artificial intelligence (the video game kind, not the Skynet kind). The game likely keeps track of all the various things that are going on, and it plays specific pre-recorded snippets of commentary depending on the situation.\n\nFor example, the game notices that team A is losing. Team A makes a play that is known to be risky and succeeds, turning the score around. The game keeps track of all of that (team A is losing, makes risky play, play succeeds), and then follows a flow chart to find the appropriate commentary, e.g. \"Look at that amazing comeback!\".\n\nIf the same thing were to happen, but the risky play were to fail, it would go down a different branch of that flow chart, playing something like, \"Looks like Team B saw what they were doing and shut them down.\" The flowcharts and commentary are all made in advanced by the game designers, who have to predict all the common scenarios that players will encounter.\n\nWhenever there's a context-specific word, such as the name of the team or the current score, the game simply has a list of recordings for every team name and every number, and it inserts the proper sound at the proper point.",
"Nice try E.A."
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3mu8d8 | how easy is it really to crack a safe? | Is it really as easy as it looks in movies where people just hold a stethoscope up to the safe and listen for the clicks? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mu8d8/eli5_how_easy_is_it_really_to_crack_a_safe/ | {
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"When UL tests safes with the goal of breaking in as quickly as possible (if the safe lasts 15 or 30 minutes it's a pass) it usually looks [like this](_URL_0_) not like the movies. And those are very experienced safe crackers with the safe's blueprints. ",
"There's a huge range of quality when you're dealing with safes, so it's tough to make a blanket statement about how easy it can be. Any decent quality modern safe is going to take more effort than just listening for clicks. That technique may have worked at some point, but safe designers know about it at this point and can design technology into the safe that makes that technique far less effective. For example, adding in mechanisms that make lots of noise/clicks whenever you turn the wheel can mask any clicks caused by normal operation. ",
"A stethoscope isn't in the safe-cracker's bag of tricks much. As /u/shawnaroo mentions, there is a huge range of things called safes. Surreptitious entry, leaving no trace, is extremely difficult. It's most often done on good mechanical locks with computer controlled number checking machines, [like this](_URL_0_ ). Electronic safe locks have different tradeoffs, they resist this kind of mechanical attack but also fail a lot more than a well made lock.\n\nAre you looking to break in someplace, or buy protection for your valuables?",
"For a safe you normally place in your home, its pretty easy given time and equipment. The key here is, that burglars don't really like spending extra time in your house, making loud noise and carrying heavy equipment.\n\nOf course no one uses a stethoscope, they use power tools. Maybe the stethoscope worked in long ago, but they most certainly don't work now.\n\nFor saves in stuff like banks, you need to ditch the power tools, and use heavy machinery, something generally not available to people breaking into a bank. ",
"Depends on point of entry. When I was a locksmith we would get calls from wealth people all the time to make sure they made the right purchase. They would literally buy one have us break into it and then buy another one depending on how easy it was. But there are many different ways to go about breaking into a safe. Honestly most safes from 200 and below are especially easy due to poor welds in the corners. Sometimes its as easy as taking a hammer to the weakest points and the welds would crack. Other safes (gun safes, large stand in safes, stainless steel, etc) have their weld game on point, usually using any type of brute force would be stupid. Also a safe with a keypad usually takes a soft reset, popping off the front panels and shorting out the computer in it would usually allow the safe to unlock(depends on brand) these tools are available only with a state security clearance ID. Other than old school lockipicking, and using stethoscopes, those are your best bets. Also im not a locksmith anymore so I cam distribute this info for \"learning\" purposes now."
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bgk6ne | why do music notes assembled in certain ways convey feelings and emotions to us? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bgk6ne/eli5_why_do_music_notes_assembled_in_certain_ways/ | {
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"For me, it has to do with what mode it is in. For example, generally music in Ionian mode sounds “happier” than music in Aeolian mode. But that doesn’t necessarily mean it’s always sounds that way. There is sad music in Ionian too. There are also chord progressions, rhythms, and a million other things. For me though, mode is the biggest indicator of mood in general.\n\nEdit: changed some mode names. Accidentally put in the wrong ones.",
"Not sure if I'm completely qualified to answer this but, remember that musical notes are just arbitrary names for a frequency and wavelength.\n\nThe reason we feel emotion when we listen to music is the same reason we do for any other activity, the release of dopamine and seratonin.\n\nIn general, music in a major key causes the release of dopamine while music in a minor key releases seratonin. Although these two things are not always true. \n\nThere are a host of various chemicals linked to their respective emotions but in short, certain types of combinations of frequencies release different chemicals in our brain."
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8wkk3o | why and how can a clear evidence not be accepted by a court? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8wkk3o/eli5_why_and_how_can_a_clear_evidence_not_be/ | {
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"This will vary from country to country. I'm assuming you're talking about the united states.\n\n > For example, certain evidences (obtained without permission) by recording someone's private conversation is turned down. Does the fact that it was obtained without permission make the evidence not true?\n\nIt doesn't make it not true, but it makes it illegally obtained. Your option is to either allow it in court and thus heavily encourage illegally obtained evidence, or to make it inadmissible. ",
"In the US it's referred to as The Fruit of the Poisonous Tree\n\nThe legal system cares about the means more than the results. If you start admitting any evidence the state can conjure up then the state can start doing whatever they want. Finding the truth isn't as important as following the rules.\n\nIt is better 100 guilty person's should escape than one innocent person should suffer. If you don't require the state to follow the rules then everyone will suffer"
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m75k1 | evolution and creationism. | i'm trying to become rather well versed in these so that i can better debate them both.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/m75k1/eli5_evolution_and_creationism/ | {
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"Science is not a debate. You debate opinions not facts. You understand facts or you do not understand facts. ",
"**Evolution** is how the world got so many different kinds of animals and plants.\n\nAnimals and plants come in many, many kinds, or *species* (like \"dog\" and \"lion\" and \"oak tree\"). They can only have babies with another member of the same species. A dog and a lion can't have babies, but a dog and another dog can. So you never see half-dog-half-lion creatures, not in real life.\n\nWhen animals have babies (or when plants have seeds that sprout into new plants) the babies are a little bit different from their parents. Some of these differences make the babies better at growing up to have babies of their own: better at staying alive in their habitat, or better at having more healthy babies. Over many many generations, all those little differences add up — and the whole species can change, as the more successful varieties show up more and more, and the not-so-good ones show up less and less.\n\nSometimes, a species can branch into two different species. This happens when two different groups of animals stay apart for a long, long time — so long, that all those changes add up in different ways for the two different groups; so much so that they can't have babies together any more. So, leopards and lions are related, but they're not the same species; you can't get leopard-lion babies. (There are some exceptions — like ligers and mules. These \"hybrids\" usually can't have babies of their own.)\n\nOver many, many thousands of generations, species of animals and plants change and branch, based on what little differences turn out to be good at keeping them alive and having more babies. And all the species on earth came about this way.\n\nThat's evolution. Evolutionary biology is the study of evolution. Evolution was discovered by Charles Darwin and a few other people in the 19th century, and the ideas of evolution have been improved and checked and updated by thousands of scientists since then. Today, scientists use evolutionary science for all kinds of things — not just studying animals and plants, but also making better food crops, and curing diseases. Evolution doesn't just describe stuff that happened to old animals and plants. It also actually works to make new things. That's how we can be really, really sure that evolution is right — if it weren't right, it wouldn't work!\n\nNow, here's the problem. Some religious people don't like evolution — because it disagrees with the Bible, or the Qur'an, or other old religious books. These books say that God created all of the world's species exactly as they are today. But these books were written a long, long time ago before anyone knew about evolution. (Most of the Bible was even written before the Ancient Greeks who proved the earth was round instead of flat. All of it was written long before Copernicus, the scientist who proved the earth goes around the sun instead of the other way around. People used to have religious arguments over that, too, but they don't anymore.)\n\nMany religious people just say that the Bible (and those other books) were just telling a special story and weren't trying to be scientifically accurate. But there are a few who say that the Bible has to be exactly true and that science is wrong. These people are **creationists.** Some of the creationists have made arguments that sound kind of like science, to say why they don't believe in evolution. But these arguments don't convince scientists, because evolution isn't just a story that Charles Darwin made up — it's something that we can actually see and use.",
"Science is not a debate. You debate opinions not facts. You understand facts or you do not understand facts. ",
"**Evolution** is how the world got so many different kinds of animals and plants.\n\nAnimals and plants come in many, many kinds, or *species* (like \"dog\" and \"lion\" and \"oak tree\"). They can only have babies with another member of the same species. A dog and a lion can't have babies, but a dog and another dog can. So you never see half-dog-half-lion creatures, not in real life.\n\nWhen animals have babies (or when plants have seeds that sprout into new plants) the babies are a little bit different from their parents. Some of these differences make the babies better at growing up to have babies of their own: better at staying alive in their habitat, or better at having more healthy babies. Over many many generations, all those little differences add up — and the whole species can change, as the more successful varieties show up more and more, and the not-so-good ones show up less and less.\n\nSometimes, a species can branch into two different species. This happens when two different groups of animals stay apart for a long, long time — so long, that all those changes add up in different ways for the two different groups; so much so that they can't have babies together any more. So, leopards and lions are related, but they're not the same species; you can't get leopard-lion babies. (There are some exceptions — like ligers and mules. These \"hybrids\" usually can't have babies of their own.)\n\nOver many, many thousands of generations, species of animals and plants change and branch, based on what little differences turn out to be good at keeping them alive and having more babies. And all the species on earth came about this way.\n\nThat's evolution. Evolutionary biology is the study of evolution. Evolution was discovered by Charles Darwin and a few other people in the 19th century, and the ideas of evolution have been improved and checked and updated by thousands of scientists since then. Today, scientists use evolutionary science for all kinds of things — not just studying animals and plants, but also making better food crops, and curing diseases. Evolution doesn't just describe stuff that happened to old animals and plants. It also actually works to make new things. That's how we can be really, really sure that evolution is right — if it weren't right, it wouldn't work!\n\nNow, here's the problem. Some religious people don't like evolution — because it disagrees with the Bible, or the Qur'an, or other old religious books. These books say that God created all of the world's species exactly as they are today. But these books were written a long, long time ago before anyone knew about evolution. (Most of the Bible was even written before the Ancient Greeks who proved the earth was round instead of flat. All of it was written long before Copernicus, the scientist who proved the earth goes around the sun instead of the other way around. People used to have religious arguments over that, too, but they don't anymore.)\n\nMany religious people just say that the Bible (and those other books) were just telling a special story and weren't trying to be scientifically accurate. But there are a few who say that the Bible has to be exactly true and that science is wrong. These people are **creationists.** Some of the creationists have made arguments that sound kind of like science, to say why they don't believe in evolution. But these arguments don't convince scientists, because evolution isn't just a story that Charles Darwin made up — it's something that we can actually see and use."
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2ufdo7 | what exactly is a mosh pit at a concert? are there unspoken rules that are followed? are there different types depending on the music? what happens if there are serious injuries? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ufdo7/eli5_what_exactly_is_a_mosh_pit_at_a_concert_are/ | {
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"Been a long, long time for me. Moshing basically throwing yourself around. The pit forms as people establish a boundary around the 'moshers' so that the area is contained. The unspoken rules are pretty simple - you can bounce off people but punching/kicking shouldn't connect with others. If someone wants out, others will push them to the edge, and the boundary-people part to make an exit. \n\nGenerally, it is pretty violent but nobody is supposed to get hurt or trapped inside when they want out. It's sort of like how armies in Greek mythology would form a circle around dueling heroes and allow them space to fight without getting involved. Can't remember the term for that... ",
"It's just good friendly violent fun for everyone.\n\nBehave like an asshole and you'll be kicked out. Literally.",
"Mosh pits are areas of playful violence that typically occur at punk rock, heavy metal, and metalcore concerts.\n\nThe standard pit simply involves people [running around and bumping into each other](_URL_0_). This is the standard at traditional punk/hardcore/crust shows but may be found elsewhere. It's interesting to not that the dynamics of pits change depending on how dense they are, too. I've been at shows where it's just a couple of people running around and I've also been at shows where people are so tightly packing that you can hardly move at all. It is not uncommon for movement in a pit to organize itself into a circle, at which time it becomes a...\n\n\"[Circle pit](_URL_1_)\", which is literally just people chasing each other in a circle and trying not to get trampled.\n\nIf you're at a metalcore, new york hardcore, beatdown hardcore, or contemporary post-hardcore show you might run into a pit that consists of \"hardcore dancing\". This involves a lot of fake karate and punching the ground and stuff like that. [It appears to have evolved from the \"slam dancing\" that was and still is common a punk shows](_URL_2_). Hardcore dancing is taboo at traditional punk and metal shows.\n\nWhile there is mosh pit etiquette they are not safe (especially if you're short and/or skinny) and people do get injured in them.When I saw Napalm Death/Municipal Waste in 2012 I got my nose broken (but, at the same time, that's the only serious injury I incurred after years of moshing). This danger is part of the appeal.\n\nMosh pit etiquette as I understand it: \n\n1) If someone falls down, pick them up. \n\n2) If someone drops something (glasses, etc) pick it up and get it back to them (or simply hold it above your head so they can reclaim it) \n\n3) Don't mess with people who aren't moshing \n\n4) No punching, kicking, throwing elbows (unless you're hardcore dancing, apparently... I don't go to those shows though so I'm talking out of my ass a little) \n\n5) The point of moshing is NOT to intentionally hurt anyone, just to roughhouse a little. People who enter pits looking to fight are assholes."
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7ax4ed | why do you wake up early and energized on days you don't have to get up to work, as opposed to normal workdays that you can't get out of bed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ax4ed/eli5_why_do_you_wake_up_early_and_energized_on/ | {
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"Bad sleep pattern I assume \n\nIf on your 'energised' days you wake up at like 10am\n\nBut your work days you wake up at 6am\n\nEven if you go to bed 4 hours earlier, your sleep schedule is still off by 4 hours. Your body needs a good sleep schedule as much as it needs a long sleep. ",
"Aka: why am I awake right now? ",
"You don’t have the mental stress of having to get up for work, that you probably don’t want to go to. ",
"Days you don't work you likely don't have an alarm so you wake up at the correct time in your sleep (when you are ready to get up during your sleep pattern). If your alarm goes off during deep sleep, you will probably feel groggy",
"If you really like your job you probably are energized. I have yet to find that job though. I guess that's why they call it work. \n\nTtyl. I got a meeting with the Bobs",
"Good call. Why did i wake up at 4:00 in the morning today, you ask? Because its Sunday and daylight savings, of course. . .",
"We sleep in cycles. There's deep sleep and light sleep.\n\nIf you're waking up to the sound of your alarm, there's no real way to predict whether the alarm sounds while you're in deep sleep or not. If you were in deep sleep at the time, trying to wake up is going to suck.\n\nIf you wake up accidentally, it'll be because you were in light sleep. That's because you're not going to wake up out of deep sleep on accident. Waking up from light sleep is much more pleasant.",
"You do?\n\nPersonally, I've been waking up tired no matter what day it is for like a year straight, perhaps more.",
"You don't like your job.\n\nCongratulations on liking your weekends though. A lot of people don't wake up early and energized on weekends. That's the healthy part of your week.\n\nGo find a job you like.",
"The weight of existential dread and depression crashing down upon you sapping your energy and will to live, while making you contemplate what is the worth of your existence as a meaningless face among millions of other lifeless drones as you get ready for work.\n\nOr it’s just that you can sleep till noon on Sunday.\n\nEdit:I’m not depressed, I was joking.",
"You wake up energized? I thought that was a lie made up by ad companies. That has literally never happened to me. Waking up is the worst part of my day everyday. If you figure it, out let me know.",
"ELI5: why do I never wake up energized? ",
"God, Mondays are the worst for me. No explanation for it, just dread getting out off bed. Most days I call in \"sick\" are Mondays. I get up at the same time to go to work Mon-Sat",
"For me personally, it's trying to sneak a few more minutes of \"me time\" because once you wake up, everything you do is for your job... From brushing your teeth to hurriedly swallowing that half-buttered slice of toast to sit in traffic and arrive at work on time.\nOn weekends, everything you do is for you upon awakening and that tends to get you excited."
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1snyqn | where do birds keep their bone marrow? | Since the bones of birds are hollow to allow for flight. Do they store it somewhere else? or is it especially light. Also, do flightless birds such as ostriches have hollow bones? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1snyqn/eli5_where_do_birds_keep_their_bone_marrow/ | {
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"According to our friends over at /r/askscience:\n\n > Birds have bone marrow it just doesn't intersperse through the central region of bones like in humans. Avian bones aren't hollow in the sense that they're like straws with absolutely nothing inside them. There are networks of structural fibers that help give their bones strength. Bone marrow is likewise interspersed and around the hollow cavities in a bird's bones.\n\nThey also linked to [this image](_URL_1_) showing a cross-section of a bird's bone.\n\n[Source](_URL_0_)"
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3yepsd | why when i'm stopped at a light and look at the other blinkers, none of the surrounding cars match up with the blinker speed of any other cars? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3yepsd/eli5_why_when_im_stopped_at_a_light_and_look_at/ | {
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"Because the cars need to have turn signals (blinkers). There is no set speed for the signal. So whoever creates the car, sets what they feel is an appropriate speed for the blink. \n\nThink about this. If you chose 5 people and asked them to draw a tree, you will see 5 different drawings of what they see when they think of tree. Maybe one will draw an oak, one may draw a pine, one may draw a palm, one may draw a bayna, and the last may draw an apple tree. \n\nBecause there is no set specifications as to what time the blinker should be, each company will chose what they perceive as the best speed. ",
"Why would they?\n\n* Each driver turned their indicator on at a slightly different time.\n\n* The length of time each indicator light is on, and the length of time it is off can be different between car makers, car models, and model years\n\n* The timers for turn indicators are not super precise (because they don't have to be) so their timing may drift faster or slower as they blink.\n\n* LED lights can go from off to on very quickly, whereas traditional turn indicator lights take a moment to ramp up to full brightness and ramp down to totally off.\n\nWhen you consider all the reasons indicators wouldn't be synced, it's easy to see why it's really hard to catch a pair of cars that *are* synced. "
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e61yoq | why are some material easier to stretch while wet? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e61yoq/eli5_why_are_some_material_easier_to_stretch/ | {
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"Like what? \n\nWater can break down/combine with many substances"
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3ehve7 | why do ringback tones have such bad audio quality? | I'm on hold, someone explain why their voices are super clear but this elevator jazz rendition of "I'll Be There" sounds like a potato | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ehve7/eli5_why_do_ringback_tones_have_such_bad_audio/ | {
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"I just steal this answer from google:\nBad Technology:\n\n\nCompanies face a collection of hurdles in delivering anything resembling quality audio over telephone systems which aren’t designed to carry music. “Land line telephone lines are optimized for voice not music.” explains Stevens, adding, “In general, many of the frequencies are filtered out in order to make sure voice quality is good. That means a lot of the high and low sounds you hear in your surround system aren’t present on the phone.”\n\n\nUn-Optimized Audio:\n\n\nFurther complicating this issue is the fact that the music is also not “optimized” for the phone systems. According to Stevens, “Fully produced music just isn’t going to sound right.” If the music isn’t optimized for the hold system, then you can experience clipping, which happens when a frequency overloads the system, leading to static and crackling.\n\n\nHardware and Software Issues:\n\n\nBut, even if the company puts thought into how they sound and looks for music that sounds good over the constricted frequencies of a phone line, there’s another hurdle — finding good hardware and software. Stevens shared that a system he recently worked with required an 8-bit mono MP3 file, which offers about the same resolution as a vinyl disc!"
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4mn6dq | if our senses are just electric signals happening in our brain, why is it that nobody has made something to trick our brains into smelling things? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4mn6dq/eli5_if_our_senses_are_just_electric_signals/ | {
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"The problem is that the brain is a huge wad of millions of neurons. Even finding the right ones to poke with a stick is incredibly difficult, and actually getting a real signal in there is even harder. It's not just one signal, it's a complex system of nose-cells, memory and interactions that is far too complex to replicate. \nThe brain isn't just a computer that takes signals, it's much more wibbly-wobbly."
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btb4qb | what happens to an oil field after the oil is pumped out? does it just leave a void/cavern? isn't it today to leave that because it could collapse? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/btb4qb/eli5_what_happens_to_an_oil_field_after_the_oil/ | {
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"Oil isn't in a big cavern underground. It's seeped into the rock, and when a hole is drilled through the pressure of the Earth compressing the rock squeezes the oil out. So when there's no oil left, there's still plenty of rock down there.\n\nIn some formations depleting the oil/gas can cause some ground subsidence, but usually nothing dangerous.",
"All the other explanations are good, but are missing the small point that when oil is pumped up to the surface, the liquid coming out is maybe 10 percent oil and 90 percent salt water. The oil is separated out and the saltwater is pumped back underground."
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1xeszb | why people have a vast vocabulary but cannot generate the appropriate words quicker in an actual conversation or debate? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xeszb/eli5_why_people_have_a_vast_vocabulary_but_cannot/ | {
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"It's because there are [several ways to _know_ a word](_URL_0_). You can know, for example, what part of speech a word is, what words are typically used with that word, how to spell the word, what it means, etc. One of the ways is the speed with which you can access the word when you want to use it. For some words, it's possible to access the word quickly when reading or listening to understand it, but when speaking or writing, the time might be much, much slower. You may have experienced this when you wanted to say a word and it was _on the tip of your tongue_. You may have even remembered at that time how many syllables the word has, and even what letter or sound it starts with, but the time taken for you to recall it and use it is much, much longer than you would like. If you _heard_ that same word, though, you would probably recognise it instantly.",
"Likely because they just don't use the words enough for them to be able to think of the word. ",
"Maybe its the same reason old people think longer before saying something. Its not because they are old and slower, its because they are going through a much larger memory and working out possible answers before speaking out.\n\nIn the same way, people with a larger vocabulary might tend to go through their word-set in their minds before answering, just to pick the right word. People with a smaller vocabulary sometimes take less time because they dont have a large set to pick from and dont have to think for a longer time.\n\nThis is just a supposition, but it kinda makes a little sense to me.",
"Knowing the meaning of a word is not the same thing as forming a thought into words. They're just not comparable tasks. Putting words to your thoughts well is quite difficult.",
"Knowing words and using words are different. Language is stored in different parts of the brain (someone else might be able to help me with all the psychology details). The biggest difference is in knowing words well enough to recognize them versus knowing words well enough to use them. Language is a behavior with different elements: listening and speaking are distinct.",
"Although someone may be better naturally than someone at debating or oratory type efforts in general. \n\nIt has just a lot to do with the fact writing and inner thought or understanding of language is completely different when you speak. Something flowing well in writing may not necessarily translate well to speech. So in a way, you have to learn what works well orally. So public speaking and the like is a real thing. You could be a master of any language but potentially falter when trying to relay your ideas orally. \n\nI could see how maybe someone with a larger vocabulary could struggle to express themselves orally since they would maybe question themselves more. But it honestly has more to do with the fact spoken language is completely different than written or understanding of words. \n\nThomas Jefferson was known to struggle with oratory efforts but was excellent with his thoughts on paper. "
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76klhy | why do people only get full once they've eaten way too much? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76klhy/eli5_why_do_people_only_get_full_once_theyve/ | {
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"It takes a few minutes for your brain to register that food is being put into your stomach and how much food. That's why when you eat too fast, you feel sick. So you need to take your time chewing to send signals to your brain and tummy that your about to fill up with food, take breaks every few minutes.",
"Evolutionarily speaking there is an incentive to eat food while it is available because much of the time it won't be available. This means that with a plethora of food available at all times we tend to overeat. Instinctively we don't desire to maintain a \"healthy weight\" because for the vast majority of our history a healthy weight was as fat as you could get. If you were slim then one bad winter could very likely kill you."
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3bhjcd | why does unplugging then plugging it back in work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3bhjcd/eli5_why_does_unplugging_then_plugging_it_back_in/ | {
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"As electronics age, the pathways change. Heat can cause this, oxidation, humidity, etc. This can cause circuits to get unstable if they depend on doing multiple tasks in a very short time. If one of those tasks gets finished too early or too late, it can wedge the whole system.\n\nThe answer is that it's usually due to instabilities. Sometimes things don't work exactly as predicted, or we predicted it wrong, or we designed it poorly.",
"Things are designed to work from the beginning of their power cycle. \n\nHopefully they continue to work indefinitely. But this are complex and can get into a state where they can't work any more. \n\nBy removing the power, you allow them to return to their default state... Which is one of working when you power them on. "
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12zs1i | why general petraeus needs to resign over this affair? | Cheating can cause problems for elected officials due to their allegiance to their constituencies, however I am at a loss as to why an individual of General Petraeus' skillset, history, and critical engagement in warfare strategy would be subject to this scrutiny. He is not elected and does not answer to the public. Why did he have to resign? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/12zs1i/eli5_why_general_petraeus_needs_to_resign_over/ | {
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"I heard on the news that it was also because the woman he had the affair with might have had access to his email and other communications related to the CIA.",
"A large reason is because the CIA doesn't want its top executive to have been black-mailed should it ever come to that over this affair. It's almost standard practice.\n\nAlso, he was pressured to resign by the FBI, who were the initial group to find out about the affair in the first place.",
"Legality aside, who would want a top spy who can't even keep an affair hidden?\n\nEDIT: I'm not condoning the affair, to be clear.",
"Government agents and officials are expected to maintain a high moral standard. This means no abuse of substances, no adultery or sex scandals of any kind, nothing. This goes for everyone from the highest official to the lowest member with a security clearance.\n\nThese issues could be points an interested party could blackmail individuals on. Let's say you're a government employee with access to sensitive information and you kick kittens in your free time. The public hates kitten kickers. If it got out that you kicked kittens, you could lose friends, family, reputation and job. I want the secrets you have, and I threaten to tell everyone you kick kittens in your spare time. You agree to feed me information to keep me quiet. This scenario is usually what happens with lower level officials. Minus the kittens.\n\nThe second issue is the more political one. It looks bad on whomever employees someone who kicks kittens. It stains everyone who has associated with them politically if the kitten kicker is high enough. It makes the ethics and morals of everyone involved and the institution itself come into question. The US government generally conducts character interviews for this reason: they don't want to employ people who could stain their reputation with kitten kicking. They don't want to deal with that at all. Security leaks are one thing, scandals are another.",
"Because if he can't keep an affair a secret then maybe having a job that requires him to keep secrets for the sake of national security isn't the best career choice",
"Don't believe everything you hear on the news. This resignation is not about an affair.",
"It's not the affair, it's that she was looking at his email.",
"The odds are that it was just a convenient excuse. ",
"Most of the stuff people have said in this thread is true, but none of that's why he HAD to resign. \n\nThe real reason is that when the CIA or any other agency that deals with classified stuff finds out that you've done something that could compromise your security clearance, it conducts a mandatory investigation to make sure you haven't been compromised, and while the investigation's going on your clearance is pulled and they either suspend you or have you do some low-level busy work. **You can't function as the head of the CIA if you're not allowed to see top secret stuff for months.** That's the real reason. It only makes sense for the CIA to conduct the investigation --- if you find out someone has been lying to you and doing some risky shit that could be dangerous for the agency, you don't just let him keep on doing his job and having access to all your secrets while you try and figure out if he's betrayed you or not, because if he is, you're letting the problem get exponentially worse. ",
"It's sad that people don't know the name of the General running a major war. Especially if their country is involved in it...",
"Remember when there was that shitstorm about some bigoted or otherwise hateful remarks that were made by some in his command. There was some sort of summit where Patraeus was summoned to WA for talks but nothing came of the incident. However, I do think it was a foreshadowing of the animosity between him and Obama. The timing makes me think this was in the pipeline if Obama got reelected. ",
"_URL_0_\nPetraeus shared classified information with her. She shared it publicly. That gets you fired. The intel community doesn't mess around with operational security. Also in the CIA affairs are ok, as long as the agency knows, the spouse knows, and the partner isn't a foreign national (limits blackmail potential). Not true in the military, infidelity is an offense one can be court marshaled for, which is why people are making a big deal to say the relationship was above board before he left the Army for CIA."
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k5262 | how and what do dogs communicate with pee? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/k5262/eli5_how_and_what_do_dogs_communicate_with_pee/ | {
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"Each dog's urine smells a little different. We can't tell, but dogs can smell much better. They're not really communicating anything different each time they pee, they're just marking their territory. It's like going around writing \"Spot was here,\" or \"This belongs to Spot!\" on every tree and fire hydrant. \nSome other dog may come along later and sniff around and be like, \"Oh, all of these trees belong to Spot.\" This might make him want to leave the area (what if Spot attacks?!), or it might make him want to pee on Spot's pee, to claim the trees as his own.",
"Each dog's urine smells a little different. We can't tell, but dogs can smell much better. They're not really communicating anything different each time they pee, they're just marking their territory. It's like going around writing \"Spot was here,\" or \"This belongs to Spot!\" on every tree and fire hydrant. \nSome other dog may come along later and sniff around and be like, \"Oh, all of these trees belong to Spot.\" This might make him want to leave the area (what if Spot attacks?!), or it might make him want to pee on Spot's pee, to claim the trees as his own."
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c8mlxn | what would be the real dangers of putting water on a nuclear meltdown? | So I watched Chernobyl and they had some nice ELI5 moments in the show but what confused me was the part where the water tanks were full and they said that if the fuel hit the water tank then it would explode again. So I tried Googling it and found some articles that says it wouldn't have exploded and the show got it wrong. So what I'm wondering is if the scientists weren't worried about it exploding then why was it such a huge deal to drain the water tanks? Especially since they state several times that water cools the fuel. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c8mlxn/eli5_what_would_be_the_real_dangers_of_putting/ | {
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"Very basically, explosions aren't always fire, simply, they're rapid expansions of matter, so in the show, they were worried about the extreme heat of the melting core touching a tank full of water. Now water when liquid is quite dense sitting in its container, but when it boils, it expands and becomes a gas (see where this is going?) so the scientists were worried that the massive amounts of water being touched by extremely high temperatures would instantly vaporise the water, creating a very rapid expansion of a great volume of water, creating a very large explosion. This explosion would cause even more damage to the reactor, totally damaging the other reactors and spreading radioactive material even further around. Hence they drained the water tanks :)",
"in the show they mention another explosion. While this isn’t physically possible to the degree the show expresses, in 1986 they didn’t know that. \n\nSuperheated fuel hitting water can cause a lot of rapid steam and hydrogen generation and can cause a steam release. However no explosion. \n\nYou have to put water on the fuel to stop a core melt in most cases. The question is usually, how much. If you put too little water on you just make more steam and hydrogen without actually cooling the fuel and risk a hydrogen explosion (see Fukushima). If you put too much on you make more heavily contaminated water and risk making a big mess of things. \n\nThe goal we have for boiling water reactors is to use around 3000-5000 gallons per minute to quench the fuel. This is high enough to cool it down even though it’s going to have chemical reactions to this, and low enough to not flood out your containment vent paths and create more of a challenge than necessary. Once the core mass is quenched you drop down to only injecting the minimum debris retention injection rate, which is the lowest amount of water required to prevent melting through the reactor or containment (typically by the time you get here it’s 200 gpm or less). \n\nThe unknown fears the engineers and scientists had in 1986 were that you might cause the reactor to become critical again and explode, or you might have a large hydrogen explosion, which not only would be a big mess on site but might also impact the other 3 reactors on site and possibly turn it into a multi reactor accident. The reality is that a melted core mass does not have the geometry and proper moderation to become critical again, and the hydrogen would be a challenge but would not be megaton level.",
"They drained the water but installed a heat exchanger. Water exchanges heat very well but what you don't want is the water vapor to take tiny radioactive particles out to the atmosphere where it can be deposited somewhere else. There was a book about the Rocky Flats nuclear trigger facility where they had a fire and attempted to put it out with fire because the proper firefighting equipment wasn't readily available. They essentially let a bunch of radiation leak out into the atmosphere as a result. That was a small fire compared to the molten mass of nuclear fuel going through meltdown. The water would be let off as steam, dry up, then the pile of hot nuclear material would melt down into the water table. Solution, install a massive radiator below the pile of nuclear material so you can relieve it of heat while not emitting radiation into the atmosphere.",
"Imagine you have a pot of boiling water with veggies on your oven. As the water heat over the minutes, your water is slowly changing state to become steam and that same gas builds presure inside the pot that will eventually become strong enough to lift the lid to let all that presure escape as your veggies are being cooked. \n\n & #x200B;\n\nIn the case of chernobyl, the pot and the lid being the nuclear reactor are both sealed togetter. As the meltdown begins, your pot starts shaking on the oven because of the presure and increase activity. In order to avoid a mess in the kitchen, you have to find a way to calm the reaction in there. Can't grab the reactor by the handle and move it away.. so you choose to add water to the pot. Just the right amount and there's enough water to calm the quick reaction but not enough and you just added more material to create steam and extrapolate the problem. \n\n & #x200B;\n\nMess up your reaction plan, the pot explodes in the kitchen and all your radioactive veggies are spreading around the kitchen and maybe even the living room. That's a shitty mess to fix. \n\n & #x200B;\n\nIn reality, some water did spill out of the pot and burned on the oven. Some bad smell in results, cleaning for sure once all is back in control but the worst have been avoided for sure. \n\n & #x200B;\n\nThe difference between half liter of water boiling in a pot and the amount of water versus their nuclear reaction in the series is the explosion is far worst than some spill in your kitchen, the whole house would've become a mess and the results would be your neibor slowly knowing you can't even cook simple steamed veggies.. after a while the whole streets knows you can't cook steamed veggies and in the URSS of 1986, not being able to cook steamed veggies wasn't acceptable."
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4rpoh1 | what's naturopathy and why are people so passionate about (or against) it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4rpoh1/eli5_whats_naturopathy_and_why_are_people_so/ | {
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"It is a pseudo science based dicipline. Some of its aspects can be beneficial, such as not eating overly processed foods. \n\nBut the homeopathic parts of it are usually new age bullshit that people buy into. There is nothing wrong with the lifestyle, until someone believes in herbal cures for real diseases. Thats how steve jobs died.",
"It is explained pretty well on the [Wikipedia entry](_URL_0_). Basically it encompasses a lot of alternative methods for improving your health or healing yourself. These methods use more \"natural\" medicines and holistic procedures rather than taking standard over the counter drugs or standard medical treatments. Some of the naturopatic remedies include homeopathy, herbalism, aroma therapy, acupuncture, and specific diets that generally include organic and non-gmo foods. \n\nThose against it usually claim that there is no evidence that any of these methods or medicines work and use of these methods can endanger the life of whoever uses it since they are not undergoing the reccomended doctor's treatment. In some rare cases, it could even effect the health and wellbeing of others around them such as in the case of refusing vaccinations allowing holes in the \"herd immunity\" that developed nations have had or refusing to take medications for mental illnesses that end up hurting others during a mental episode. \n\nThose supporting it usually have positive personal experiences with naturopathy or very negative experiences with general medicines and tend to distrust the organizations and institutions that provide most of the data about the methods or provide the medicines themselves. ",
"Naturopathy in that name has only been around since the late 1800s, though it promotes itself as going back further.\n\nThe issue with naturopathy and other alternative medicines is that they abuse vulnerable people for money. People who sell magic water to somebody with cancer are fucking scumbags.\n\nFor an actual ELI5 on the issues, X-pathy is a pretty broad category so it's hard to say what all of it is. A lot of modern medicines come from natural sources, like aspirin or pennicillin.\n\nIf I chew on willow bark instead of taking an aspirin pill is that naturopathic? Because it's objectively worse than taking the pill, since there's no way to control for purity or dosage.\n\nHerbalism really illustrates the \"Alternative medicine that works is called medicine\" adage. There are probably unknown beneficial properties to plants, but if they're discovered they're isolated, synthesized, and made into pills. Medicine. In that case naturopathy is just taking untested unregulated supplements from a shady dealer and hoping there's some unknown beneficial property to it.\n\nOther stuff relies on pseudoscientific concepts like homeopathy (water memory), chiropractic (joint and nerve alignment causing general unwellness), energy waves and orgon and shit, etc.\n\nTo answer the actual question, the reason people hate it is because it's snake oil and it's stealing money from people who feel they have nowhere else to turn. Kids have died when their parents put them through chelation therapy (A dangerous treatment for acute heavy metal poisoning) to cure autism.\n\nThe reason people are so into it is too long for this post, but it's the same thing as conspiracy theories, religion, etc. People have what you'd call grand narratives, overarching beliefs about the world, and they gravitate towards things that confirm their narratives. Many people mistrust things like big pharma (not without cause, but big pharma being a bunch of scumbags doesn't mean plant magic cures cancer) or the government, and that gives them a very strong incentive to believe ideas that reinforce those things.\n\nThat's why people say Mexicans are lazy but also say they work horrible jobs for barely any money. They contradict internally but they confirm the grand narrative that mexicans are bad so the contradiction doesn't matter.\n\nMistrust of people in power is a huge nexus of crazy-ass beliefs and people who have that mistrust will gobble them up. The antithesis of that mistrust, trust in \"nature\" and \"natural sources\" is equally strong and likewise pulls people towards things they think are natural. \n\nFor a laugh, read some of the literature testing over-the-counter herbal supplements. There's basically no regulation and even really simple ones like echinacea and shit frequently have none of the advertised active ingredient. There's a very good chance when you buy herbal supplements that you're buying literally nothing."
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7wphpu | if the us deficit continues to grow, what happens? what's a worse case scenario? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7wphpu/eli5_if_the_us_deficit_continues_to_grow_what/ | {
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"It’s all about the interest payments. If the debt becomes too large for the US to pay at very good credit rating, then the rate at which the country borrows will go up. If that happens, the amount of the payments will go up drastically and the US will pay a higher and higher percent of budget on interest. The more you have to spend per year to pay off debt, the less you have for other things. This tends to have a snowball effect and can easily lead to less tax revenue coming in because the government is spending less on things like new boats, roads, bridges, things that are tied to employment. Also, in the event of a recession or depression, the country needs the ability to borrow and stimulate the economy to minimize the recession. If the country is borrowing at a very high rate before a recession begins, then they have less room to borrow when the time comes that borrowing is needed. This is what economists are freaking out about right now. The economy did not need an infusion of cash from the recent tax bill from December. Borrowing like you are in a recession makes it hard to borrow when you really need it."
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7nq316 | why aren't gasses of the atmosphere dispersing into the vacuum of space? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7nq316/eli5_why_arent_gasses_of_the_atmosphere/ | {
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"Just borin' ol' gravity. Without it our atmosphere would drift away in hours. But even air has *some* weight, enough fer our planet's substantial gravity ta hang on ta it. (And our magnetic field protects it from bein' blasted away by particles zoomin' out from the Sun. Arrr!)"
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48la7n | the concept of precession of the equinoxes? | No matter how much I read about it I just can't understand it! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/48la7n/eli5_the_concept_of_precession_of_the_equinoxes/ | {
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"Precession is the rotation of a rotating axis. Like this spinning top here:\n\n_URL_0_\n\nThe gyro is spinning along its axis, but the axis itself is rotating too. This happens with Earth too, although it's a bit slower than in the video. About one cycle per 26 000 years.\n\nBecause the axis of the Earth is tilted, the plane of our equator doesn't intersect with the Sun all the time. (Imagine the red plate from the video extending to infinity, this is what the plane of equator is) The plane intersects the Sun exactly twice every year, and those are called equinoxes. And now because the axis is precessing, the equinoxes don't happen exactly at the same time every year."
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38cy41 | why is variety in passwords still valued over length in so many places when a long password has clearly been proven to be harder to crack than a fancy one? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/38cy41/eli5_why_is_variety_in_passwords_still_valued/ | {
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"Most of the people responsible for web security aren't being paid to read every article in every security journal or web blog. They're lucky if they get to go to one security conference a year, and even then, they might not attend the session on good passwords. Since they may think that using a complicated password is already the generally accepted best practice and one that they've already implemented, they're more likely to look at articles concerning new threats.\n\nCombine this with the marketing perspective that requiring special characters gives the appearance of higher security. Users have already been programmed to expect to throw in a digit and odd character. Some of them will believe, erroneously, that requiring a 16 character password but not requiring at least one special character is the sign of a less secure web site. ",
"I seriously hate these morons that set revolving passwords. That's by far, the WORST possible attempt at security outside of no security at all.\n\nWhat's the first thing someone does when they have to keep changing their password every month or two? They write it down...and there's your fucking security right out the window.\n\nAnyone that really knows security understands that you need users to create a very strong password that doesn't change unless an actual need to change arises or is suspected. When doing this, you only have to set a lockout for too many wrong password attempts. Only administrative accounts should be changed regularly.\n\nSome people just don't get it. Had another IT guy try to prove me wrong and ended up filing a complaint when I took his twenty bucks on a bet by socially engineering my way into 2 out 4 office workstations by finding the password written down somewhere at the desk. "
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4s7joj | why are protesters allowed to block off roads and highways? | A quick Google search didn't say much, other than "because its easier to let them". Is this really all there is to it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4s7joj/eli5_why_are_protesters_allowed_to_block_off/ | {
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"Pretty much. When people gather in large groups, arresting them is a huge nuisance - and can often transform the situation into a riot. So the police normally try to get the protesters to disperse rather than arresting them.",
"There really not unless they had a parade pemit or something similar. The right to assemble is afforded to citizens in the US via the Constitution, that has limits though creating a dangerous enviroment being one. Municipalities have different ordinances, but in general as long as it is temporary and isnt endangering the public or protesters it is 'allowed'. Quashing every protest wouldn't bode well for those in power and they'd be voted out next election. "
]
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a8v9kx | why does a can of shaving cream get colder after you shake it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a8v9kx/eli5_why_does_a_can_of_shaving_cream_get_colder/ | {
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"I've never noticed them getting colder after shaking but pressurised cans usually get colder after you use them because when you let some of the contents out, the mass inside expands to fill the same volume of container. When gas expands it cools down.\n\n...away to shake a can just now",
"Expanding gas acts like an air conditioner and cools things down. A CO2 fire extinguisher when used causes ice to form in the same way"
]
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jq1a6 | li5, what kind of game is it exactly, and how do you play dungeons and dragons? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jq1a6/li5_what_kind_of_game_is_it_exactly_and_how_do/ | {
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"_URL_0_\n\nThat's a pretty good overview, ignore the bits about the movie.",
"It's like cops and robbers or playing house. With guidelines if you play right. With rules and rulebooks if played wrong. ",
"_URL_0_\n\nThat's a pretty good overview, ignore the bits about the movie.",
"It's like cops and robbers or playing house. With guidelines if you play right. With rules and rulebooks if played wrong. "
]
} | [] | [] | [
[
"http://www.reddit.com/r/explainlikeimfive/comments/jkx20/eli5_dungeons_and_dragons_and_what_the_movie_had/"
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"http://www.reddit.com/r/explainlikeimfive/comments/jkx20/eli5_dungeons_and_dragons_and_what_the_movie_had/"
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23b5ti | why are catholics not supposed to eat meat on good friday? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/23b5ti/eli5_why_are_catholics_not_supposed_to_eat_meat/ | {
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"It is basically the remnant of a bunch of different traditions. It used to be customary to fast on all Fridays throughout the year in commemoration of Good Friday as a form of penance. A long time ago, meat was very expensive and few people ate meat every day; most ate fish or other foods. So as a form of penance it became tradition to abstain from meat during the Friday fast because meat was a luxury.\n\nWhat remains of that tradition is a less intense sort of fast on Fridays throughout Lent and (generally) and more intense fast on Good Friday. It is kind of odd because a lot of meat is cheaper than a lot of fish, but alas. \n\nIt should also be noted that it is simply a tradition, not a mandate. Lent is a time for penance and you do what will bring you closer to God. Different Catholics hold the tradition to varying degrees. As with any religion's traditions there are also plenty of people who have completely lost sight of the point of it and just do it - hence people \"abstaining\" from meat and having lobster instead. I know plenty of fellow Catholics that do it and get a lot out of it, plenty that do it and probably get nothing out of it, and plenty that just don't do it."
]
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[]
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1o0xfv | what is the difference between being a line cook and a chef? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1o0xfv/eli5_what_is_the_difference_between_being_a_line/ | {
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"Cool, that makes sense. I recently became the kitchen manager of my restaurant six months ago, the only reason why is because everyone else who worked there quit. But I make new recipes constantly and everyone calls me chef, but it feels weird. ",
"A line cook follows a recipe to prepare a dish.\n\nA chef sees what foods are available, creates recipes to utilize those foods, assembles those recipes into a menu, instructs the cooks how to prepare them, delegates tasks during the dinner rush, prepares food as necessary, and spot checks food as it goes out."
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[],
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j5nj2 | can someone explain to me money markets to me like im 5? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/j5nj2/can_someone_explain_to_me_money_markets_to_me/ | {
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"It's no different than a regular savings account, just higher minimum balances which usually yield higher interest than a simply savings account. It is not linked to any external risks, most Money Market account's are FDIC insured. Rates are generally 25-50% better than the average savings. It differs from a Cetificate of Deposit (CD's) because you can take the money out when ever you like with no penalty on the interest, up to 2 times a month. ",
"It's no different than a regular savings account, just higher minimum balances which usually yield higher interest than a simply savings account. It is not linked to any external risks, most Money Market account's are FDIC insured. Rates are generally 25-50% better than the average savings. It differs from a Cetificate of Deposit (CD's) because you can take the money out when ever you like with no penalty on the interest, up to 2 times a month. "
]
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[],
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1wb6nn | why do we still use tooth brushes? | i see adds for some animal teeth cleaning sticks and such, why haven't humans invented a less tedious way of cleaning our teeth by eating something or doing something besides rubbing pointy plastic on them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wb6nn/eli5_why_do_we_still_use_tooth_brushes/ | {
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"text": [
"There has been no great market pressure for anybody to come up with anything different. So nobody has.",
"Getting teeth as clean as they should be is actually a rather difficult task. Imagine cleaning a fork with your eyes closed. Its quite easy to miss a bit. The bits you miss get caked on and more difficult for the day after. Now imagine up to 32 of these beasts. Hidden surfaces as they all join together. Difficult access. Possibly making you gag. Etc etc. Some people do it very well but most are terrible. \n\nTo then assign some automated quick easy machine to do the same as what is required of such dexterity is asking a lot. Electric toothbrushes take some of the chore out of it but flossing etc still needed so no real short cut. \n\n3d printed gum shield type brushes are new and claim to do it in 6 sec. More evidence required. _URL_0_\n\nI suppose like cutting hair and various other tasks it will be a while off before we get a bot to do the same as what we can. "
]
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[],
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"http://www.telegraph.co.uk/news/newstopics/howaboutthat/10356089/3D-printed-toothbrush-that-claims-to-clean-teeth-in-six-seconds.html"
]
] | |
1njail | how do people make caffeine free tea leaves? any drawbacks compared to the non-caffeine-free, less vitamins, antioxidants, etc? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1njail/eli5_how_do_people_make_caffeine_free_tea_leaves/ | {
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"text": [
"Either a low caf plant is selectively bred (genetically engineered) or the caffeine is extracted with a solvent. Both options still contain caffeine, only significantly reduced amounts. I would assume (conjecture) that removing caffeine chemically would result in some loss of other substances."
]
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[]
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cwgh3z | why do our bodies have the ability to dislike food when we need it to live? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cwgh3z/eli5_why_do_our_bodies_have_the_ability_to/ | {
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"Because food can be dangerous and disliking it makes it less likely that you'll ingest it and risk poisoning.",
"Bodies are not identical and their needs change throughout its lifetime. Unknown underlying weaknesses and diseases can be exacerbated by consuming the wrong foods. Dislike for foods are sometimes clues.",
"In nature, bitter or sour flavours can indicate poisonous, inedible, burnt or rotten food. Notice how lot of people don't like bitter foods - such beer or unsweetened coffee - the first time they try them, but they gradually start to appreciate them because their brain gets to know they aren't harmful. The same goes for cheese, some people just can't stand the smell and taste cause their brain thinks it's rotten milk. Stuff like blue cheese is liked by even less people cause it has mold, another thing your brain wants to avoid.\n\nFor the rest of flavours, it's mainly because the abudance of food we have made us picky. If we can choose between different foods, we are wired to go for the ones that have the highest nutritional value, so food with lot of sweet taste or umami taste (which generally indicates high fats and proteins).\n\nHunger is the best spice in the world and lot of people never experience true hunger, which only kicks in after like one day of fasting."
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bbzbq2 | how can the us charge julian assange with a crime if he is not a citizen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bbzbq2/eli5_how_can_the_us_charge_julian_assange_with_a/ | {
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"text": [
"Because not being a citizen of a country does not give you free reign to commit crimes against it. That would be a ridiculously huge liability and risk.",
"Not being a citizen doesn’t exclude you from justice. It just means you’ll likely be expelled from the country after you serve your sentence. Assange committed crimes against the US government and thus they’re requesting he be extradited to US soil to face justice. \n\nWhether you and I believe Assange is innocent is irrelevant, as he has to come answer to the charges regardless."
]
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4vv1lq | why do so many us stores have chip card readers that aren't activated? (meaning, i still have to swipe my chip card) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4vv1lq/eli5_why_do_so_many_us_stores_have_chip_card/ | {
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"text": [
"Because many gateways have not finished certifying with the various processors on the backend. So in many cases the stores have the hardware and are ready, and are just waiting for their POS and/or gateway provider to support EMV.",
"Because either the company that makes the software they use or their banks don't offer it. \n \nAlso, chip cards require a bit more data, so if a business has slow-ass DSL, the \"authorizing\" time can be quite long. I've been to some places where it was 3sec and others where it was 15sec. So, a business that does a lot of quick sales (like the SUBWAY on my university's campus, ordering bars on opposite sides with 30 people in each line) choose not implement them."
]
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4f1x2h | how do "personal" charities like the "bill and melinda gates foundation" work? | With all the talk about personal charities, I've been curious about them. How much of a tax break do they give? Is it up to the founders to decide how the money is invested? What are some other interesting facts and consequences of this practice? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4f1x2h/eli5_how_do_personal_charities_like_the_bill_and/ | {
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"Hi, I actually have one of these in the United States.\n\nWhen you donate money to it, you get a tax break as if you'd donated to any other charity. \n\nYou can be the head of it, or appoint others to run it. However, by law, the money can only be used for charitable purposes -- and the penalties for ignoring that law are severe, since the IRS knows there's a temptation there.\n\nYou can also decide how to invest the money is invested until it's donated. Again, there are severe penalties for abusing that, such as investing in yourself.\n\nThe charity can employ you, or anyone you choose, for legitimate jobs like managing the donations or the investments. It can also pay for moderate expenses, like sending you on a trip to investigate ideas for donations. So a rich family could theoretically use the charity to give their lazy grandchild a job while still getting a tax deduction. Again, the IRS is watching."
]
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7ngohs | how do semitruck drivers know what route to take to avoid overpasses that are too low for the truck? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ngohs/eli5_how_do_semitruck_drivers_know_what_route_to/ | {
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"GPS systems normally know the height of every bridge and just discount that stretch of road so the mapping algorithm has to find a different way",
"Interstates must have a clearance no less than 16 feet. In cities it can be 14 feet, but some route through it must still be 16. States generally also have these standards, or something very close, and the handful of exceptions to them on state routes are available online, in atlases, and on truck GPS systems.\n\nSo if you've got a normal semi, and you use the highways and observe signs about truck restrictions, you're good to go. If you've got something taller than this, or an oversize load of any kind, it's a special case, and you've probably worked this out in advance before you start driving. If there's an accident or something that forces you to detour, you just be really careful.",
"Every country typically has an agreed upon lowest available height on all roads.\n\nHere in Sweden, that height is 450cm (about 14.5ft) and the rules surrounding it are pretty simple;\n\n- Vehicles with a height of 450cm should be able to pass. Everywhere.\n\n- All exceptions have really thorough signs warning way ahead, suggesting a good diversion and so on. To, you know, uphold the most reasonable convenience.\n\nTo make it easier for everyone, there are road maps with all the non-standard bridges marked. And if you buy a satnav intended for trucks, they also got that information.\n",
"They read the signs, well sometimes, they have hit things before \n\nMost trucks state the height on them, though that can change depending on how heavy their load is, or if they say have a bucket truck and don’t lower the arm down all the way",
"Trucker GPS. You can enter your truck height, weight and width. It’ll automatically avoid those route/roads that does not fit with your truck.\n When i was new on my job driving truck I didn’t have GPS for truck and I almost want to quit that day(local Chicago route). "
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1001sk | the teacher's strike in chicago | Why are they on strike? More money? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1001sk/eli5_the_teachers_strike_in_chicago/ | {
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"It's very tough to find an answer on this one. While CPS has been pretty open about what they're offering, CTU has been much less open about what they're offering. Here's what I've been able to puzzle out:\n\n1. Re-hiring of fired teachers. Some teachers are fired because the schools they teach at close. Later, when other teachers need to be hired, these former teachers want preference for the new jobs. CPS says they can apply like anyone else, and they already have a leg up because of previous employment.\n\n2. Teacher assessment. The state passed a new law requiring school districts to change their teacher assessments. CPS and CTU got together to come up with a new assessment measurement. Now, CTU doesn't want to use it(or wants to use very little of it, I'm not sure which). \n\n3. Control. CTU argues that it's really the principals and the higher-ups that are causing poor school performance. They also argue, however, that principals and higher-ups shouldn't be allowed to choose teachers for their schools. CPS argues that principals should be allowed to choose their teams.\n\n4. Classroom time. I think that CPS is offering 7.5 hour school day, 180 instruction days a year, 10 in-service days a year. CTU wants less than that, although I don't know what.\n\nThose are the ones I've been able to figure out. "
]
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[]
] | |
dqfi5r | why our phones don't make any machinery noise like laptops and pcs make? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dqfi5r/eli5_why_our_phones_dont_make_any_machinery_noise/ | {
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"Our phones have no moving parts whatsoever besides the vibration mechanism.\n\nLaptops and PCs have fans to cool the CPU, etc while cell phones will use a simple heat sink for cooling.",
"Because their battery is so small, phones use electronic components designed to really minimize power use. This means they don't need a cooling fan."
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bdu1ta | how does your heart(body) get used to training. | I’m a younger guy and get tired easily. I see some older people that are just in amazing shape.
I’m starting to get better but I’m curious how our bodies change. I mean, I know our hearts don’t get any bigger...
Thanks! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bdu1ta/eli5_how_does_your_heartbody_get_used_to_training/ | {
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" > I know our hearts don’t get any bigger...\n\nWell...\n\nWhen you do exercice, your heart adapt itself throught physiological cardiac hypertrophy. In simple words, your heart gets (slightly) bigger, your ventricules gets wider and so does the muscle : It makes it so that your heart can send more blood to your organs with less contractions (The amount of blood send by your heart in one minute is relatively constant and therefore if you can send more blood because your ventricules are wider, you need less constraction to send the same amount of blood, not sure if it's clear, english isn't my first language).\n\nThat's why sporty people have slow heart rates (around 50-60) next to non sporty people (more like 70-75).\n\nThis phenomenon is different than pathological hypertrophy thought : When you have high blood pressure, your hearts needs to work harder to fight against this pressure and your ventricule will contract with more force, it makes your ventricule muscles grow wider but it \"eats away\" the ventricular cavity and makes it so that you need to contract your heart more often to send the same amount of blood. Given enough time, it leads to severe heart failure.",
"I used to be a bit on the heavier side a couple of years and have really gotten into fitness and cardio especially (endurance runner). I run on average 40- to just under 60 miles per week and it's a matter of your body getting used to the training. \n\n & #x200B;\n\nI didn't just wake up one morning being able to curl a 40 pound dumbbell or go out and run 3 miles in an instant. It took training for me to be able to do. I slowly built up to the challenge. \n\n & #x200B;\n\nOvertime, your body becomes more efficient. My heart rate has lowered because it has become more efficient in pumping blood. My recovery from my lifts are faster since my body is used to it. \n\n & #x200B;\n\nJust go into a workout and ease into it. Overtime, your body will get used to it and you will become better in shape.",
"As you go from a larger size to a more athletic build, your body will change in many ways. Your heart might not get noticeably bigger, but your veins do!\n\n1) Your body will be smaller. The farther your heart has to push your blood, the more energy and harder it works.\n\n2) Your body grows bigger veins that go further into your muscles. It's like trying to put out a burning building from a small garden hose to to a fireman's hose.\n\nThe more efficient your heart and veinous system, the less energy it uses.",
"Overall idea: Use it or lose it. The body is energy efficient. Not using that muscle? Deflated. Not using those bones? Brittle. Eating lots of food? Better save as much as I can. Astronauts don’t need much muscle or cardio fitness in space and their bodies deteriorate pretty badly. Your body on earth is doing the bare minimum fighting gravity and stresses to keep you upright and alive.\n\n\nMuscles: Inside those cells are mitochondria that convert food to energy. The more you use it, the more mitochondria you’ll make. Stop using it, they deteriorate and go away. Your muscle cell walls will also increase their sodium pathways to make fast twitch actions faster (reaction times). \n\nBones: As you walk around you create cracks and stress points on your bones. Your osteocytes find those brittle and cracked areas and reinforce them with calcium to make sure they don’t break. Stop using your bones (walking has a lot less stress than running) and your bones will deteriorate from daily stress and won’t be patched up. Make them strong by stressing them from bouncy sports like running and weight lifting.\n\nCardio: Bigger veins and capillaries cost energy and resources to maintain. As your exercise, your muscles and bones will demand resources at a faster rate, and your circulatory system will respond by increasing in girth and pathways to get the oxygen and food where it’s needed. Get sedentary and everything will constrict and harden up to save on space and maintenance costs.\n\n\nOverall: The more oxygen and nutrients your body demands, the more will body will grow to get stuff there efficiently. As you exercise you’ll feel tired and produce stress hormones. Your cells will read this and start fixing itself, patching cracks and building channels to get water O2 and nutrients to where they’re needed. Your veins will feel the increased traffic and start expanding to accommodate the demand. Your lungs will have to clean out the cobwebs to get more oxygen into the blood ASAP.\n\n\nYou’ll get HUNGRY. That is until your body finds a point where it’s business as usual, though it’s a more demanding one. \n\n\nOf course, when you stop exercising your body will naturally want to save energy and start packing on the pounds.\n\n\nThose old people running around looking slim are that way because their bodies are efficient and used to it."
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kfhpq | why does software "bloat" and generally get crappy over time? | It seems like for the last 20 years I've been in a constant state of upgrading, tweaking, hot fixing, patching, uninstalling, defraging, formatting, and generally getting under the hood of my PC like it was a cheap car from the 1950's. My question is... why are computers designed like this, why does software have to be so... delicate? There has to be a better way to go about this, if we could do it over again knowing what we know now would there be a fundamental shift in how software is coded or is it just sort of the nature of the beast to be inherently unstable? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kfhpq/eli5_why_does_software_bloat_and_generally_get/ | {
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"Basically the problem is actually that things are advancing but not at the same time.\n\nOkay programmer rarely make something purely from Scratch. They tend to build upon some else work. This is because no one want to reinvent the wheel each time they want a persons mouse to move the cursor on the screen.\n\nSo let's taking just moving a mouse for instance. The first mice had one button. So a person at say Microsoft wrote a piece of software that made it easy to use a mouse that used one button. We'll call this software version 1.\n\nNow someone is like 2 button is better for a mouse. So Microsoft make a software called version 2. Version 2 support mice with one button and two button. \n\nIf your making new software you'll use Version 2 because it supports both two button mice and one button mice. But alot of lazy programmer won't bother changing their software and keep using Version 1.\n\nNow new features are added, we've got optical mice, we've got three button mice, scroll wheel mice, touch screen mice, tablet suddenly your up to Version 12 and the code is getting really complicated. In Version 1 for example alot of old computer needed something Serial to control a mouse, but now everyone uses something called USB. The serial part of your code is really old and no one really understand it any more. There is a decision at Microsoft to remove Serial support from Version 13 because it's slowing everything down and no one uses it.\n\nBut now you have a problem. Some program are using still using Version 1, their programmers are that lazy and some people really need to use software that using Version 1. Some people need version 7 for some reason. And people with Serial Mice need version 12 cause version 13 doesn't work with their mice.\n\nSo now programmer start including multiple Versions of the mouse software in their software. If they want everyone to be supported... well they have to. Now their program is starting to get bigger because of all different version they have to include, and it's running slower as well. This is where Bloat happens.\n\n",
"It's not really an inherent feature of software itself, more a feature of the social structures around software. Hang on, you're five...\n\nOk, suppose a software company has a great piece of software, FooBar 6, which everyone buys and uses. Suppose one day they said \"Ok great, FooBar 6 does everything we wanted it to. Now we're just going to find bugs and release patches to fix them\". That's great, but the thing is, they never make a FooBar 7, so no-one gives them any more money, and they go out of business. As a business, you earn more money for your effort from releasing new versions and getting people to pay for an upgrade, than you do from either making new programs from scratch or fixing bugs in your existing programs. So the programs get bigger and bigger, with more and more features (and more bugs too, since you're putting them in faster than you're removing them).\n\nSo, is this a thing all software must do? Not really. In Free and Open Source Software, there's no financial need to keep adding new features and releasing new versions. There's still a bit of a problem, because most of the people writing it write for fun, and most people find it more fun to write new features than fix existing bugs, but the problem isn't as bad. A program like [Vim](_URL_1_), the text editor, has been in continuous development for about *20 years*, and isn't bloated and full of bugs. The [TeX Typesetting System](_URL_0_) is another great example of bloat-free Free Software. IIRC, they got up to version 3 and decided they were basically done, so they said that there would be no version 4, and their version numbers would now asymptomatically approach pi. The latest versions is version number 3.1415926, it's full-featured, rock stable, and apparently bug-free. If you can find a bug in TeX, the author will give you $327.68.\n\nSo it can be done, but there's a strong incentive in commercial software that causes this trend.",
"Let's say you decide to build a house. The requirements for that house will depend on your current situation. So say you are young, single, and in an entry level job. A small 2 bedroom, 1 bath house with a small yard would be plenty of room and cost less to keep. That would make a great choice.\n\nTime passes. You get a better job, get married, and have kids. You could build an extension on your house, refinish the basement, build a garage and a storage shed, but at the end of the day, it was originally designed to be a 1 person house. The changes you make will always be a little awkward, and it will never be as good as a house custom built for a family.\n\nSoftware is the same way. The first version is designed to one set of requirements. Each subsequent version brings new requirements, which may or may not work well with the original design. There is also a marketing issue...the new version has to add something, or people will stick with the old. A lot of times these new features are bloat most people don't need. ",
"Basically the problem is actually that things are advancing but not at the same time.\n\nOkay programmer rarely make something purely from Scratch. They tend to build upon some else work. This is because no one want to reinvent the wheel each time they want a persons mouse to move the cursor on the screen.\n\nSo let's taking just moving a mouse for instance. The first mice had one button. So a person at say Microsoft wrote a piece of software that made it easy to use a mouse that used one button. We'll call this software version 1.\n\nNow someone is like 2 button is better for a mouse. So Microsoft make a software called version 2. Version 2 support mice with one button and two button. \n\nIf your making new software you'll use Version 2 because it supports both two button mice and one button mice. But alot of lazy programmer won't bother changing their software and keep using Version 1.\n\nNow new features are added, we've got optical mice, we've got three button mice, scroll wheel mice, touch screen mice, tablet suddenly your up to Version 12 and the code is getting really complicated. In Version 1 for example alot of old computer needed something Serial to control a mouse, but now everyone uses something called USB. The serial part of your code is really old and no one really understand it any more. There is a decision at Microsoft to remove Serial support from Version 13 because it's slowing everything down and no one uses it.\n\nBut now you have a problem. Some program are using still using Version 1, their programmers are that lazy and some people really need to use software that using Version 1. Some people need version 7 for some reason. And people with Serial Mice need version 12 cause version 13 doesn't work with their mice.\n\nSo now programmer start including multiple Versions of the mouse software in their software. If they want everyone to be supported... well they have to. Now their program is starting to get bigger because of all different version they have to include, and it's running slower as well. This is where Bloat happens.\n\n",
"It's not really an inherent feature of software itself, more a feature of the social structures around software. Hang on, you're five...\n\nOk, suppose a software company has a great piece of software, FooBar 6, which everyone buys and uses. Suppose one day they said \"Ok great, FooBar 6 does everything we wanted it to. Now we're just going to find bugs and release patches to fix them\". That's great, but the thing is, they never make a FooBar 7, so no-one gives them any more money, and they go out of business. As a business, you earn more money for your effort from releasing new versions and getting people to pay for an upgrade, than you do from either making new programs from scratch or fixing bugs in your existing programs. So the programs get bigger and bigger, with more and more features (and more bugs too, since you're putting them in faster than you're removing them).\n\nSo, is this a thing all software must do? Not really. In Free and Open Source Software, there's no financial need to keep adding new features and releasing new versions. There's still a bit of a problem, because most of the people writing it write for fun, and most people find it more fun to write new features than fix existing bugs, but the problem isn't as bad. A program like [Vim](_URL_1_), the text editor, has been in continuous development for about *20 years*, and isn't bloated and full of bugs. The [TeX Typesetting System](_URL_0_) is another great example of bloat-free Free Software. IIRC, they got up to version 3 and decided they were basically done, so they said that there would be no version 4, and their version numbers would now asymptomatically approach pi. The latest versions is version number 3.1415926, it's full-featured, rock stable, and apparently bug-free. If you can find a bug in TeX, the author will give you $327.68.\n\nSo it can be done, but there's a strong incentive in commercial software that causes this trend.",
"Let's say you decide to build a house. The requirements for that house will depend on your current situation. So say you are young, single, and in an entry level job. A small 2 bedroom, 1 bath house with a small yard would be plenty of room and cost less to keep. That would make a great choice.\n\nTime passes. You get a better job, get married, and have kids. You could build an extension on your house, refinish the basement, build a garage and a storage shed, but at the end of the day, it was originally designed to be a 1 person house. The changes you make will always be a little awkward, and it will never be as good as a house custom built for a family.\n\nSoftware is the same way. The first version is designed to one set of requirements. Each subsequent version brings new requirements, which may or may not work well with the original design. There is also a marketing issue...the new version has to add something, or people will stick with the old. A lot of times these new features are bloat most people don't need. "
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3alb0k | what on earth is the logic behind the format of the questions in jeopardy!? | I mean, it seems like you're meant to answer with a question, but as far as I can tell the player just gets read a list of facts by the host and has to name the 'thing'. If you reverse it it makes no sense as a question and answer.
BTW We don't have a British version of the show. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3alb0k/eli5_what_on_earth_is_the_logic_behind_the_format/ | {
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"It's a gimmick. Instead of asking \"boring\" trivia questions (\"who was the first man on the moon?\" \"Neil Armstrong\"), the questions are formed as answers, and the answers as questions (\"he was the first man on the moon\" \"who is Neil Armstrong?\").\n\nIt also makes the questions a bit harder - if you are too concentrated on thinking about the answer, you might forget to form it like a question.\n\nEdit: typo."
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1z731f | how do dividends work if i buy stock? | I just bought my first group of stocks online and I opted to reinvest dividends to take advantage of compound growth. I haven't found any real clear explanations of how dividends are paid or earned. Please help, I need an adult. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1z731f/eli5how_do_dividends_work_if_i_buy_stock/ | {
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"Ok.\n\nSo dividends are kinda cool. Basically, once a quarter (so 4 times a year) some (but not all) companies will pay a dividend. This dividend is a way for the company to pay out some of its revenue/profit to its owners (the people who own its stock).\n\nSo let's say you own Company A which is worth $100 per share. They announce a 5% dividend. Each share you own will pay out $5 (5% of $100) to your account.\n\nWhat you've chosen to do is say \"don't give me cash, give me more shares\". So instead of getting those $5 a share... you get 1/20 of a share of Company A's stock. If you own 20 shares, when they pay the dividend you'll now own 21 shares.\n\nPretty cool.",
"It's actually fairly abitrary. The board of directors can pay dividends any time they like just by voting to do so. In practice it's a lot more controlled than that, typically some stocks will pay them rather regularly as a way to attract and reward investors, others will pay them when they have a particularly profitable quarter. It's similar to a sole owner taking profit home as income rather than using them to buy more equipment or services to grow the company.\n\nMore good reading here: _URL_0_",
"Companies choose to pay out a portion of their profits (or horded cash) to investors from time to time. This is called a dividend. Some stocks pay them regularly, others pay them only from time to time, and still others never pay them. \n\nDividends are usually paid out as a certain amount of money per share owned. If you own 10 shares, and a $0.10/share dividend is declared, you would be paid $1 (10 * $0.10). \n\nSome people choose to receive their dividends in cash. In that case, the dividend will be placed into your investment account or you will receive a check in the mail with the dividend.\n\nOther people choose to have their dividend reinvested in the stock (DRIP - Dividend Reinvestment Program - is the name for this). If the dividend is reinvested, the money that would have been paid to you is used to buy (usually fractional) shares of the company, which is added to your stock ownership. \n\nAnd advantage of DRIP is that you are not taxed on the dividend. You are only taxed the capital gain on the shares that the dividend purchases when you sell.",
"It's easy. A dividend is a share of a company's earnings and profits (E & P). They come in a number of flavors, but can be classified as \"regular\" or \"special\" for most purposes. A \"regular\" dividend is paid periodically—usually quarterly or annually. A \"special\" dividend is a one-time, non-recurring deal.\n\nDividends are traditionally paid out in cash, but more recently, companies have offered stock reinvestment dividends, which means you receive additional shares instead of cash. The number of shares you receive is equivalent to the cash value of cash you would otherwise receive, which generally means you'll get fractional shares. So it's a great way to grow your stake in a company without having to buy extra shares. You can, of course, elect to change your mind at pretty much any time.\n\nGenerally speaking, the dividend proceeds—cash or stock—will be \"paid\" into your brokerage account.\n\nDoes that help clear things up?",
"Not sure I saw this elsewhere, but assuming you hold your shares in a non-tax exempt account (ie not a 401k, IRA, Roth IRA, other retirement account) and you're not a non-profit, you're going to be taxed (somewhere between 20-25% depending on your income level) on the dividends that get reinvested. You won't get the cash, but you'll have to pay taxes on it. Now, if your portfolio isn't that big, its not a huge problem. If you have $10k and your stocks yield an average of 2%, you're only looking at $10k *.02 *.25 = $50 in taxes due. ",
"Stock Dividends - are cash payments usually paid once every 3 months. The amount varies by company. Generally speaking older more established companies pay more in Dividends than newer less established companies which may not pay any dividends. Also, dividends vary by industry. Again generally speaking, Utilities, Commodity sector companies and Real Estate related companies tend to pay higher dividends than industrial or technology oriented companies. \nA board of Directors can also delclare, Special Dividends in lieu or or in addition to the regular dividends. Special dividends can be paid for a variety of reasons although companies usually pay special divs when the company has a significant amount of cash and no immediate plans to use it. \nIn contrast to dividends Capital Gains is the increase in price of a stock from where it is trading at the time you purchased it and the price at the time you sold it. For example you buy XYZ stock for $50/share on x date; you sell it 366 days later for $100/share. Your capital gain is $50 per share. Capital gains are dictated by the markets and the prospects for the business of the company whose stock is being traded. "
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1q6pg0 | if pangaea was on one side of the globe, would the earth have had trouble spinning on its axis? | During the late Paleozoic and early Mesozoic eras (300-ish million years ago) all the landmasses were joined together as the super-continent Pangaea.
With all this extra mass on one side of the globe, would this have affected the earth spinning on its axis? Attaching a weight the the side of a spinning top makes it go all wobbly... | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1q6pg0/eli5if_pangaea_was_on_one_side_of_the_globe_would/ | {
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"~~The average weight of the oceans balances out the average weight of the landmass. Moving the landmass is like shifting the weight on one side of a spinning top, but the oceans shift to fill the space formerly occupied by the landmass, keeping it even.~~\n\nEDIT: this is not incorrect, but it is not the best possible answer, which is that the total combined mass of land and water which would be shifting is insignificant compared to the total mass of the Earth. It could be analogized as being like shifting the peel of an apple - the effect in relation to the entire apple is insignificant. We have actually seen [this effect as a result of earthquakes like the one that caused the Fukushima tsunami](_URL_1_), but it is negligible.\n\n[The best answer is here](_URL_0_), courtesy /u/demodawid",
"The effect wouldn't have been very noticeable. The earth's crust is a TINY fraction of the entire mass of the earth (less than 1%).",
"If Earth was shrunk down to the size of a billiard ball, it would be smoother than one. I'm guessing not much effect by the crust dynamics. \n\n[source](_URL_0_)\n"
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2zkqgh | if all bodies (moons/planets/suns/galaxies) etc are moving at speed, does the accumulated speed increase the mass of the universe? | If everything stopped moving (at a macro) level, would the mass of the universe decrease? Or is the speed of those bodies still too low to have mass applied to them (as they would if they could approach the speed of light)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2zkqgh/eli5if_all_bodies_moonsplanetssunsgalaxies_etc/ | {
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"Rest mass and relativistic mass are not the same thing.\n\nRest mass doesn't change with velocity. It stays the same.\n\nRelativistic mass is a confusing term, as it really means \"the total energy\" of the thing, which does increase with velocity.\n\nIf everything stopped moving so fast, the total energy would decrease, but the total rest mass would still be the same.\n\n[The \"m\" in E=mc^2 is relativistic mass. The E is relativistic energy, for that (ha) matter.]\n\n(Bonus: The relativistic mass is related to the rest mass by a certain factor. As velocity gets closer to the speed of light, this factor increases faster and faster. Which means it takes more and more energy to increase that velocity. Which means the particle has more and more inertia. Which means it's *as if* it had more mass. Hence the term \"relativistic mass.\" But total energy is a better way of thinking of it.)"
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ai4g02 | how can credit card companies afford to give away so many travel points? | When my fiancée opened up her Chase credit card, they gave her 50,000 travel points.
How can companies afford to do this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ai4g02/eli5_how_can_credit_card_companies_afford_to_give/ | {
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"They make an absolute fuck ton of money on interest\n\nThose points giveaways are likely loss leaders...similar to how Costco sells a full cooked 3 lb rotisserie chicken for 5 bucks\n\n\nThey'll make much more hand over fist in interest charges in the aggregate",
"Easy..\n\nEvery time you use that card the business that takes it is charged a % of every sale. That money then goes back to rewarding customers at a LOSS to the customer. After all, the card company is in it to make money for themselves.\n\nSuppose you buy $100 worth of stuff at store X. If you use your credit card they charge the company a % (based on the average sales..) so let's say they charge that company 97 cents. Then you, the customer gets a reward.. but your reward is equal to only 50 cents. The card company makes profit.\n\nNow.. I note you don't pay more for using your cards.. except if you pay fees - which also go back in part to this system.\n\nOverall small businesses might pay several hundred dollars a month to credit card companies.. large businesses pay thousands.",
"The CC company is making way more money off you having and using your card then they give back to you in points or otherwise.\n\nCC companies often take 2-3% of each purchase (its complicated) as a fee to the merchant for using your card to pay. Even if they give you back 1% or so, they are still making 1%-2% off just the transaction, let alone plenty of other way to make money, such as their big money maker, interest.\n\nBut how can they offer it in the first place? Well, the CC industry is ultra competitive, and in many ways, its a race to the bottom, you need to get customers to stay alive, and one of the best ways to do it is to offer incentives and such to get customers and be willing to take a lesser amount from each customer (but have more customers overall to compensate)"
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1stxqh | computers. how could people make a pile of metal "understand" bits of code and do an action according to that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1stxqh/eli5_computers_how_could_people_make_a_pile_of/ | {
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"Humans write code. Code gets read by an operating system, which sends more detailed instructions to hardware like the video card. Video card takes instructions and translates them down into very basic impulses which can run through specially-designed circuits.\n\nIt doesn't really \"understand\" any more than a ball \"understands\" to roll down a hill. It's just physics, creatively applied.",
"This blows my mind also. I would pay to understand it. ",
"It fundamentally comes down to the millions of transistors in the microprocessors which can take electrical signals and process them into other electrical signals, utilizing magnetic memory to save states. It really is quite incredible that, using this basic building block, we can make all sorts of really incredible things.\n\nHow Stuff Works has a bunch of really good ELI5 summaries, most of which are contained in or linked to in their PC article: _URL_0_",
"It comes down to logic gates. Little switches that turn on or off based on input. For example, an AND gate will only be switched on if both its inputs are on. There's a great book that goes into it in depth called \"Code: The Hidden Language of Computer Hardware and Software\" It's by Charles Petzold, and it's written in a way that is very easy to understand for lay people. Highly recommended if you want to develop a good understanding of basic computing.",
"Computers don't understand anything, nor do they \"do calculations\" in the same way a human does (although this is debatable).\n\nWe've observed that certain physical mechanisms mimic some very simple mathematical processes. We've figured out how to duplicate these mechanisms and shrink them down to a very small size, and how to link them together to mimic more complicate processes. That's all a computer is.",
"It starts with a transistor. A transistor is basically a piece of electronic that has 2 states, on or off - think of a light switch. If its on, electricity passes. If its off, electricity doesnt pass. So, with one transistor, you can represent 2 values - on or off, true or false, 0 or 1. It can be whatever you call it. This is called a bit. \n\nSo, we add more transistors. With 2 transistors, you can represent 4 values (00,10,01,11), with 3 transistors you can represent 8 (000,100,010,001,011,111,101,110) and so on. As you can see, more transistors you have, more data you can store. We can also do calculations with transistors, using logic gates. Dont forget that there are two possible values, 0 or 1, and it just so happens we have a perfect way to do math with them- it is called boolean algebra, and it was invented about 100 years before the first computer.\n\nOk, now you have a pile of silicone and metal that can hold data and do calculations. The first computers were entirely hardware based and they used levers or punchcards for input. Back then, programming was organizing the transistors in correct positions to do calculations. The input you make was represented with zeroes and ones, this is called the machine language. Years and years later, after some serious technological advances, this was deemed too hard and time consuming. So what they did is basically bind long and complicated inputs into smaller, more understandable (relatively) words. For example,\n \n 0100101010 01110101010101 010101 \n\nbecame \n\n MOV AL, 1h \n MOV CL, 2h \n MOV DL, 3h \n\nThis went on for years, then one day someone decided to go one step further and created the first modern programming language. Now, the subject of which language is the first programming language is up for debate. To put it simply though,\n\n MOV AL, 1h \n MOV CL, 2h \n MOV DL, 3h \n\nbecame\n\n test1 = some_function();\n if (test1 > 0)\n test2 = 0;\n else\n test2 = other_function();\n return test2;\n\nAnd this is where we are today, more or less. See how much easier it is to read, compared to the others? It actually has english words in it. Nowadays, we have smart compilers and IDEs, and programming is easier than ever. Back in the day, you would write your code, compile and pray. ",
"First to clear up a misconception, computers have no \"understanding\" like we do. They don't read code in the sense that a human might read words on a paper. There's no thought of any kind involved. This is a somewhat tough ELI5 since you really need a decent amount of background knowledge so that computers don't seem like magic. That said none of the concepts necessary are actually all that difficult.\nGenerally we denote a low voltage as a \"0\" and a high voltage as a \"1\". This is defined because it is useful to do so. What the actual voltages are is irrelevant at the moment. A single bit (binary digit) is used to represent these two states. By chaining enough bits together it is possible to represent an arbitrary number, which is known as binary. \n\n\nThe most basic component of modern day computers are tiny little gizmos known as transistors. Transistors are actually far more complex than switches, but in digital circuits they're primarily used as voltage controlled switches. There are two types (this is a very gross simplification, there are many types!) that we think about. By arranging these transistors we can implement a variety of circuits. \n\n\nSome other responses have already alluded to logic gates, which are an important concept (though there are other important components as well). Let's say we have a two input AND gate. Each input is a single bit (a 0 or 1) and it has a single bit output. An AND gates output is 1 if both inputs are 1, either wise its output is 0. An OR gates output is 1 if either input is a 1. These gates are arranged in such way to form more complex circuits like a 1 bit adder (which is a very simple circuit). To understand a 1 bit adder a more in depth explanation of binary math is required so I won't go into it. Just remember we can use a sequence of bits to represent numbers. We can then say chain a 1 bit adder to be say a 32 or 64 bit adder (remember we can represent numbers using bits). You can then imagine that it may be possible to build a subtractor/multiplier/divider. This is the very very basics of how your computer is performing math. The important thing to realize is that it's almost mechanical, we have inputs (bits) and the circuits are designed so that the correct answer must appear at the output of the circuit.\n\nWe've established a bit about how math is performed, but wait. How are any actions taken? How does your computer \"decide\" what to do. Well who says binary has to be used to elusively represent numbers for math operations. We can also use binary numbers to represent instructions. So I may have several kinds of instructions, such as add these two numbers, compare these two numbers, skip to some other set of instructions, etc. There set of instructions is known as an instruction set. A modern processor has a ridiculous number of instructions it is capable of operation on. The fact that different CPUs (say ARM CPUs vs x86 CPUs) have different instruction sets is one of the reasons why code written for one hardware platform can't run on another platform. To execute these instructions a different arrange of the previously mentioned logic gates can be constructed. It would take in a given instruction and figure out how to get the appropriate result passed out. It would use of the other circuits such as the adder if the instruction said to add for example.\n\n\nNow, we have an element of computers known as memory. A CPU fetches an instruction from memory. It then decodes the instruction and dispatches it. It may decide to skip several instructions, add some numbers, crash your computer, compare some numbers etc. These results are then written to memory. The CPU then fetches the next instruction. This process repeats indefinitely.\n\nI've left a lot out (most of a major's worth). But those are some of the fundamentals to grasp. If you want to understand how transistors work, go take solid state physics. Those thing are black magic.\n\nHope that helps!\n"
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36lenh | what "secret" societies exist and what are their purpose? | For example organizations like Knights Templar, Freemasons, Skull and Bones, etc.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36lenh/eli5_what_secret_societies_exist_and_what_are/ | {
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"Those are no secret societies since you can name them. And we can't tell you about the real secret societies because, well, that's a srcret that we don't know about.\n\nNow, as for their goal. The usual, global domination, power over the masses, controlled consumerism, money, power, and on rare occasions destruction of all/some of mankind. \n\nEdit: grammer",
"Well, the Knights Templar are long gone, and we know about the Freemasons and Skull & Bones, so they aren't that secret. \n\nHere's the truth about secret societies and conspiracies: they are only as secret as the people in them are willing to keep them, and people love to blab. \n\nAs Benjamin Franklin said, \"Three can keep a secret, if two of them are dead.\" And that's why conspiracies and secret societies never last. Once it goes beyond three, there's no keeping it a secret. \n\nTL;DR: Relax. There are no secret societies."
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fsiy8c | why do drill bits that are cutting into metal in commercial or industrial settings remain stationary, while the piece of metal spins? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fsiy8c/eli5_why_do_drill_bits_that_are_cutting_into/ | {
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"That would be typical when drilling something chucked up in a lathe. The chuck turns, like a regular drill, but it holds the work piece instead.\n\nMachines like a radial arm drill press will rotate the drill bit, and not the workpiece.",
"What you are thinking of is specifically a lathe, which is used for circular cuts and working of a material (there are different types of lathes for wood and metal). Since lathes spin the metal so that it can be cut and shaped on the outside, there's no need to have the drill bit spin as well. \n\nSpinning the bit at the same time means more moving parts to fail, more stress on the motor for having to drive those parts, and more stress on the drill bit and worked metal, which could damage or break either.\n\nIn terms of physics, if the metal or the bit is spinning, as long as one of them does. it's just easier and smarter to keep spinning the worked metal.",
"If you bore a hole with a fixed tool (boring bar) and rotating workpiece, you can create any diameter hole without having a drill of exactly that diameter. A boring bar with an adjustable hole diameter is asymmetrical, so it wouldn't be balanced if it was spinning. Thus, machinists spin the workpiece instead. This custom led to using the same technique for drills with radial symmetry, even though it's not necessary."
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4lhibk | why was michelangelo hired/allowed by the pope to paint god on the ceiling of the sistine chapel, while it is forbidden to create an image of god by the ten commandments? | "You shall not make for yourself an image in the form of anything in heaven above or on the earth beneath or in the waters below." Exodus 20,4 NIV | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4lhibk/eli5_why_was_michelangelo_hiredallowed_by_the/ | {
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"The simple answer is \"different religions interpret the bible differently\". Also keep in mind that the sentence you quoted up there is one variation of translation of a translation of a translation. \n\nTo get more specific, the images painted, along with icons and other representations are just that - representations. They're not actually pictures of God. They can't be, because we don't know what God looks like. \n\nObviously some religions, and some factions of the same religion might disagree on the interpretations. For example, there are some Jewish orthodox painters who say that since God made us in His image, you shouldn't paint *people*. One of them is famous for painting planks of wood wherever people should be. ",
"Not everybody interprets it that way, though. And in fact, you only quoted part of that commandment. The full commandment is:\n\n > You shall not make for yourself an image in the form of anything in heaven above or on the earth beneath or in the waters below. You shall not bow down to them or worship them; for I, the LORD your God, am a jealous God, punishing the children for the sin of the parents to the third and fourth generation of those who hate me, but showing love to a thousand generations of those who love me and keep my commandments.\n\nThere are different ways of interpreting this. The strictest interpretation is the one followed by the strictest Muslim sects: a complete ban on pictures of anything in the real world. That's why so much Islamic art is abstract.\n\nHowever, most Christian theologians don't interpret it that way. First of all, the word translated by the NIV as \"image\" really refers to something carved out of wood or stone -- the more traditional \"graven image\" is actually more accurate here. But even that's not all there is to it, because the Old Testament is full of God-approved graven images (the Ten Commandments are placed inside the Ark of the Covenant, built to God's own specifications including carved angels). Secondly, the first two sentences probably should be one -- when the Old Testament was written, punctuation hadn't been invented, and sometimes it's difficult to tell where one sentence ends and the next begins.\n\nThe most likely interpretation is: \"You shall not carve out of wood or stone anything that looks like anything that exists and then worship it.\" In other words, this is a commandment against idolotry, the making of artificial gods and worshipping them. Israel was unusual at the time in *not* worshipping statues: they claimed that this was because their God existed for real, whereas other \"gods\" were merely lumps of wood. So, by order of God himself, don't worship lumps of wood -- it explains the \"I am a jealous God\" bit.\n\nSo, most Christians interpret this commandment as a ban on idol worship. You can make images of anything you like, as long as you don't *worship* them."
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508bfp | why are coffee cups in tv/movies so blatantly empty, rather than filled with weight? | In most shows I've seen, it's obvious that these coffee cup props are completely empty by the way they move, or by the sound they make when set on a surface. This wouldn't be that big of a deal, except for the brief disruption of immersion.
In my attempts to search for previous ELI5 questions about this, it's obvious that filling opaque coffee cups with liquid isn't a good idea because of potential spills, as well as the amount of liquid an actor would have to ingest throughout all the takes required.....but my question here is different: Why not just simply fill them with a solid weight, like a gelatin with a similar density as water, to more realistically mimic the way these objects should move? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/508bfp/eli5_why_are_coffee_cups_in_tvmovies_so_blatantly/ | {
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"And the million dollar question you have to answer: does that add anything to the storyline of the film for the avg filmgoer? No.\n\nJust like movies never say goodbye when hanging up the phone, never lock the door, cock the gun even on a gun that doesn't cock, hacking by typing furiously at the keyboard, looking at a screen so bright the reflection off the glasses is blinding, 10 bad guys fighting the hero will take turns attacking, bad guys have absolutely no aim when shooting, bad guy has to explain the entire evil plan for 5minutes before attempting and failing to kill the good guy. ",
"It's called suspension of disbelief. If you're more focused on coffee cups or any other container that holds liquid, rather than the conflict of the scene, the film/tv show/stage production isn't doing its job. Or, you're too focused on a small detail and letting that blind you from what's going on. Question everything in theatre, but focus on what's vital and what relates to you, the audience member.",
"Professional IATSE feature film cinematographer here... The issue of liquid in the cup is really up to the actor. Some actors prefer some liquid in the cup for realism and others are paranoid to drink anything on set or don't want to drink from a dirty props cup. The way it works is right before we roll cameras (like seconds before) someone with props will hand an empty cup to the actor. It's really no ones job to be sure it's filled with anything (especially if it's not a clear cup) so no one cares. On a film set you quickly learn to worry about your job and your job only. The actor will need to request someone fill their cup just as well roll. Then everyone scrambles to find an unopened water bottle. \n\nInterestingly, on the film I am shooting right now the we are shooting a party scene every single night with hundreds of extras (with cups!) and our prop department is going the extra mile and filling every cup when they are handed out. So on this movie the cups are full! But indeed on most movies they are empty. ",
"_URL_0_\n\nFor comparison"
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