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9955j6
How does Captcha know the solutions to all of its tests?
Technology
explainlikeimfive
{ "a_id": [ "e4kz58h", "e4kyx20" ], "text": [ "For the funny looking text, the first version of Captcha would just be keyed with the answer. For the next version, reCaptcha, there were 2 words; one was like the first, a key word where they knew the answer, and another word that was scanned with optica...
[ "url" ]
[ "url" ]
998big
why are loading bars inconsistent?
Technology
explainlikeimfive
{ "a_id": [ "e4loz70", "e4lowy1" ], "text": [ "To be completely honest with you, programmers don't really care about loading bars being accurate. We only put them there to stop impatient users from assuming our programs crashed, forcefully killing the process, and permanently messing up something. An ...
[ "url" ]
[ "url" ]
99e0t8
How are modern day planes able to land even in thick fog?
My flight today landed in fog that reduced the visibility down to just 50 yards. How does modern technology allow for this? And why is it that some flights are still delayed due to fog?
Technology
explainlikeimfive
{ "a_id": [ "e4muukt" ], "text": [ "Depending on the plane some have auto-land systems (not joking). There’s Instrument Landing Systems that guide the aircraft down to 100-200 feet above ground. These airports usually have pretty bright runway edge lights and runway centreline lights that shine through fo...
[ "url" ]
[ "url" ]
99ed75
Why do so many businesses still require documents to be faxed?
Technology
explainlikeimfive
{ "a_id": [ "e4mynwq", "e4mygux", "e4mz2jl" ], "text": [ "As far as banks go, it's liability to their systems. When you have 10s of thousands of employees opening attachments to emails, there's bound to be something malicious eventually. You may not think so, but banks spend a fortune on technolog...
[ "url" ]
[ "url" ]
99exzu
In terms of computing technology such as servers and "the cloud", what happens when you play online video game which connects to other players?
Technology
explainlikeimfive
{ "a_id": [ "e4n339s" ], "text": [ "Video games are just a bunch of equations being run by computers. That doesn't change whether the game is on your console or in the cloud. If you're playing a console game, some of that processing is being done on your console and shared in real time over the internet. ...
[ "url" ]
[ "url" ]
99fa53
How does fiber optic works?
Technology
explainlikeimfive
{ "a_id": [ "e4n5ygc", "e4n5v73", "e4ntlui" ], "text": [ "The fibre optic cable is made of glass in a way that traps light inside, even as it goes around corners. Pulses of light are sent in one end, and detected at the other end. The pulses can be very, very short, allowing very high data transfe...
[ "url" ]
[ "url" ]
99fhc2
What makes a video cinematic?
Technology
explainlikeimfive
{ "a_id": [ "e4o27rn" ], "text": [ "A lot more time, effort and expense it put in to each step of the cinematography process. Lighting is crucial. Movies take time to light each shot just right, allowing shadows to fall just so. TV shows will tend to be more \"light everywhere\" so the camera/actors can m...
[ "url" ]
[ "url" ]
99gtro
Why multiple processors vs one larger processor
So these days the new generations of both CPUs and GPUs are integrating more cores/processor cores. So Why is this a better approach vs having one or just a few larger cores if multi-tasking is the concern? In my uneducated opinion, each more core introduces more over heads; and typically the more cores there are, the ...
Technology
explainlikeimfive
{ "a_id": [ "e4nl9wr", "e4nnshk", "e4nj94t" ], "text": [ "Processors are basically made out of silicon which is a ~~high conductive metal~~ [semiconductor]( URL_0 ) [metaloid]( URL_1 ) and as any other material, it has some physical limitations. Imagine a rubber band holding a deck of cards. You c...
[ "url" ]
[ "url" ]
99k5zk
Why is water cooling advertised as silent for computers but the radiator has fans in it?
Technology
explainlikeimfive
{ "a_id": [ "e4obi3v", "e4ocwrn" ], "text": [ "Marketing is a kind of temporary reality that ceases to exist the minute you buy something.", "Nothing with moving parts can be silent **but** you can use multiple larger, slower, quieter fans on big watercooler's radiator to get the same (if not bett...
[ "url" ]
[ "url" ]
99l1te
What are these 12 letters or number you often found alongside their username in online forum? Something like 24DAFA:DA4FEA.
Technology
explainlikeimfive
{ "a_id": [ "e4py119" ], "text": [ "Hexadecimal codes (a method of counting in base 16). Don't really know what they might represent in said forums. User ID perhaps?" ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
99ncec
Why do some electronics go senile?
Technology
explainlikeimfive
{ "a_id": [ "e4oymlz", "e4p37rg" ], "text": [ "Aside from dying batteries, one of the biggest causes of electronic failure are capacitors. As they get older, they can leak (both electrically and physically), which causes them to stop working properly, and possibly damage other components around them."...
[ "url" ]
[ "url" ]
99t2yi
How does the film in an instant Polaroid camera work?
How does the image just appear onto the film almost instantly? Is the ink stored in the film?
Technology
explainlikeimfive
{ "a_id": [ "e4q8bbt", "e4qc11g" ], "text": [ "Top comment 8 months ago got 7400 upvotes: URL_0", "theres no “ink” in a polaroid film packet. the thick bottom part of the border holds the chemicals, the rollers in the cameras burst the packet then spread it along the photo to develop it. URL_0 has...
[ "url" ]
[ "url" ]
99uonw
Why do airplanes get shaky when passing through clouds?
That might be false but that's just based on most of my observations in the plane...
Technology
explainlikeimfive
{ "a_id": [ "e4ql9ek", "e4qqyaf", "e4qq1pk" ], "text": [ "Think of the atmosphere like it is millions of balloons. There are pockets of balloons that are different temperatures, and the warmer ones rise to the top. Clouds have different temperatures and humidity, so the contrast is more noticeable...
[ "url" ]
[ "url" ]
99uqt2
How come cars don't use a smaller-sized battery nowadays?
Do we really still need the big box battery to start our cars? If so, why?
Technology
explainlikeimfive
{ "a_id": [ "e4qobbh", "e4qo8yj", "e4rmhoy" ], "text": [ "You need lots of amps, you need it to be cheap, it must widthstand hard discharge and recharge cycles and harsh environments, and, since weight and size aren’t a problem here, lead acid batteries are the way to go, since they do all of thy ...
[ "url" ]
[ "url" ]
99uvk9
When you take a picture of your computer with your phone, the screen is blurry and has weird black lines. How come?
Technology
explainlikeimfive
{ "a_id": [ "e4qmo45", "e4qo5c4" ], "text": [ "Screens create grids of colours to create the display that we see. A digital camera looks at a grid of points and records there colour. If they two grids are aligned, all is good. If the two grids are offset then then bad things happen: Pixels are mixed, ...
[ "url" ]
[ "url" ]
99w9m2
What does non polarized phone display mean?
& #x200B;
Technology
explainlikeimfive
{ "a_id": [ "e4qusqe" ], "text": [ "Light can be thought of as a wave. An electric field turns into a magnetic field and back. The relationship between these fields means that light can be 'polarized' or have all the little wiggles happen in the same direction. Polarizing filters can block out light so th...
[ "url" ]
[ "url" ]
99xqfo
Why was the graphical jump from ps2 era to the next generation so large compared to what we see today?
Technology
explainlikeimfive
{ "a_id": [ "e4r5d4s", "e4r5gdh" ], "text": [ "Same as the reason for the jump before that was bigger still. Going from black and white to colour is huge. Going from static images to moving images is huge. Going from 2D to 3D is huge. Eventually, the huge things are taken care of. Going from harsh to ...
[ "url" ]
[ "url" ]
9a50is
How do calculator batteries never run out?
I've had the same calculator for the past 5 years and it's never died or anything, so how do they never need new batteries?
Technology
explainlikeimfive
{ "a_id": [ "e4st0ca", "e4ssyun" ], "text": [ "Calculators use very little power, so it's battery lasts many years. Some calculators have a small solar panel which can usually generate enough electricity to power it - the battery is only there as a backup and so it can last for many more years without...
[ "url" ]
[ "url" ]
9a635t
Why are industrial power generators 3-phased? Why not 1 or 2 phases, what's so special about it?
Technology
explainlikeimfive
{ "a_id": [ "e4t6hf7", "e4sztgp", "e4t0nxp", "e4tep50", "e4tflx1", "e4thr9n", "e4sz62x", "e4th40v", "e4ts7wo" ], "text": [ "It's like riding a bike. Two-phase power is equivalent to a two-pedal bicycle, and there are moments & mdash;when one pedal is all the way up and the ...
[ "url" ]
[ "url" ]
9a713b
How do oil powered engines actually work?
i know i can simply google it but i cant make it go inside my head and understand it, how a simple liquid powers up an engine just by pouring some oil on it, why others liquids like water wont power it up.
Technology
explainlikeimfive
{ "a_id": [ "e4t67rg", "e4tcc1i" ], "text": [ "Well fuel cells work with water, but that is a different discussion. Basically oil explodes when you light it on fire. You light it on fire by giving it a spark or compressing it really fast. When it explodes it gives of heat. If you have taken a chemistr...
[ "url" ]
[ "url" ]
9a9dx7
Why are TV applications so slow? We have tiny smartphones with super fast processors, so why are these not matched in Smart TVs?
Technology
explainlikeimfive
{ "a_id": [ "e4tp45x", "e4tp68j" ], "text": [ "I think there are a couple of factors. 1) usually anyone who can get a smart tv has some other box that does these things better, therefore 2) not putting a top-of-the-line chipset in a TV cuts down on cost and allows them to sell panels for a cheaper pri...
[ "url" ]
[ "url" ]
9a9nb0
what is "The "Cloud" and how is it different than the internet?
Technology
explainlikeimfive
{ "a_id": [ "e4try1c", "e4tqv4l" ], "text": [ "Back in the day, we used to just call it a “server”. Or “remote host”. Then, a few years ago, somebody invented this cuddly term to appeal to the common man.", "The Internet is a global, connected series of networks that share common communication pro...
[ "url" ]
[ "url" ]
9a9t94
How do the calorie counters work on things like treadmills? Are they accurate?
& #x200B;
Technology
explainlikeimfive
{ "a_id": [ "e4tt2ba", "e4tu6rt", "e4tw15n" ], "text": [ "They're ballpark estimates based on average weight body shape person. So no, they're not accurate", "If you're inputting your weight, they're accurate enough. Calories are a measure of energy, and the treadmill can calculate the amount ...
[ "url" ]
[ "url" ]
9acif8
Why does a 4k video on a 1080p screen looks better than a 1080p video on a 1080p screen?
Technology
explainlikeimfive
{ "a_id": [ "e4uffy7", "e4ui983" ], "text": [ "Supersampling and antialiasing. the idea behind that is that is this, imagine you have a straight diagonal line on the screen that you draw pixel by pixel, since the pixels have a finite size there will be points where the line will jump to the next row. ...
[ "url" ]
[ "url" ]
9ae596
Why do companies like Verizon work so hard to limit customers internet usage?
Technology
explainlikeimfive
{ "a_id": [ "e4urt1r", "e4utzhb", "e4ut8do", "e4us2p8", "e4utaot", "e4utga1", "e4uu1v5", "e4utwas", "e4uu9sm", "e4uudbg" ], "text": [ "Money. They don’t want to invest in infrastructure so they throttle customers to save costs.", "I switched to T-Mobile over 55 plan...
[ "url" ]
[ "url" ]
9aekn3
how does signing something with PGP confirm the authenticity
Technology
explainlikeimfive
{ "a_id": [ "e4vbebw" ], "text": [ "In regular cryptography, you use the same key for encryption and decryption. If that key is compromised, you can both create and read all the messages made using it. With a public key system like PGP uses, there are two keys, one to encrypt and one to decrypt, and knowi...
[ "url" ]
[ "url" ]
9aenm2
What is Geofencing?
& #x200B;
Technology
explainlikeimfive
{ "a_id": [ "e4uuo86", "e4uyq0s", "e4v81hy" ], "text": [ "The wikipedia page explains this well : > A geo-fence is a virtual perimeter for a real-world geographic area.[1] A geo-fence could be dynamically generated—as in a radius around a point location, or a geo-fence can be a predefined set of b...
[ "url" ]
[ "url" ]
9aeptg
How does the internet work so insanely fast?
I'm an IT student and I don't understand this shit. If I ping [ URL_1 ]( URL_0 ) from Australia it takes 240ms to go from my computer to Sydney to Tokyo to somewhere in Taiwan I think and back again. It has 16 "stops" between me and the destination. Doesn't something have to happen at each of the "stops" that would tak...
Technology
explainlikeimfive
{ "a_id": [ "e4uxp5j", "e4uxfxm", "e4uw1a1", "e4ve97r", "e4vufiz", "e4uxr36", "e4w4f1j", "e4uxa32" ], "text": [ "There are two parts to this: how long it takes the signal to travel the physical distance involved, and how long the \"routing\" takes (the logic needed to decide wh...
[ "url" ]
[ "url" ]
9af4va
How do they come up with thousands of puzzles for puzzle games?
& #x200B;
Technology
explainlikeimfive
{ "a_id": [ "e4uxvm4" ], "text": [ "Usually by finding a theme that can be varied a bit in multiple ways and then building suites of related puzzles, which also lets them implement difficulty curves. Also, there have been countless puzzles already invented, some very classic. You can get a lot of your wor...
[ "url" ]
[ "url" ]
9agccu
What happens if you take your phone off of airplane mode on a plane?
Technology
explainlikeimfive
{ "a_id": [ "e4v6r8w" ], "text": [ "Nothing. It's just that they want to minimize any potential risk of interference from 100+ cell phones on the plane. Even then, most of the electronics of the airplane are pretty well shielded against things like that." ], "score": [ 10 ], "text_urls": [ ...
[ "url" ]
[ "url" ]
9agcvq
How are the raw images sent back from space probes processed in such a way to give a vibrant and colourful image?
Let's use Saturn as an example. [This is a raw image from Cassini]( URL_0 ), and [this is a processed image]( URL_1 ). Additionally, if I was to jump in a space ship and fly out to Saturn, would it look like the second image?
Technology
explainlikeimfive
{ "a_id": [ "e4v80lt", "e4v83d2" ], "text": [ "Cameras aboard spacecraft like Cassini take photos using filters that isolate different wavelengths on the electromagnetic spectrum. Some, like red, green, and blue, capture light the human eye can see. Others, like ultraviolet and infrared, capture light...
[ "url" ]
[ "url" ]
9ahdub
Why do self-checkout machines sometimes need “assistance?”
Technology
explainlikeimfive
{ "a_id": [ "e4vfvhn" ], "text": [ "Sometimes the customer operating the self-checkout don't follow prescribed steps, so the machine calls for assistance. For example, not placing a scanned object in the bagging area without indicating that you are going to skip bagging will call for assistance. Or becaus...
[ "url" ]
[ "url" ]
9ai0sx
If a person on TV is talking to someone across the country/world why does it take seconds for the other person to respond when seamless video chat over internet has been a thing for year?
Technology
explainlikeimfive
{ "a_id": [ "e4vjmly" ], "text": [ "In these cases, it's because they are talking via *satellite* instead of fiber-optic Internet connection. Communication satellites are so far from Earth's surface that there's a noticeable delay." ], "score": [ 12 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
9ak3x9
Why do the machines at the laundromat occasionally reject my quarters?
Technology
explainlikeimfive
{ "a_id": [ "e4w1rpo" ], "text": [ "Machine senses what type of coin based on it's weight. Machine is designed for heavy use not 100% precision. Quarter weight is inaccurately measured first time so it's rejected, put in again and is measured correctly, you get clean clothes." ], "score": [ 3 ],...
[ "url" ]
[ "url" ]
9al5ga
How are modern day CPU's or GPU's designed?
Technology
explainlikeimfive
{ "a_id": [ "e4wb2k9" ], "text": [ "There is a circuit programming language called [VHDL]( URL_0 ) (VHSIC Hardware Description Language -- VHSIC stands for Very High Speed Integrated Circuit but sometimes the 'v' referred to Verilog in the past) that allows digital circuits to be designed in code and simu...
[ "url" ]
[ "url" ]
9aoqsy
How does Strict NAT and UPNP affect online connectivity while gaming?
Technology
explainlikeimfive
{ "a_id": [ "e4x0o0h" ], "text": [ "NAT or Network Address Translation is basically a way for your router to handle translating private/local IP addresses (192.168.x.x/172.16.x.x/10.x.x.x) to public addresses. Without it, each device on a local network would either need a public IP address, or would not b...
[ "url" ]
[ "url" ]
9aqd2t
How does the EAS (Emergency Alert System) work?
I tried reading about it on Wikipedia but I end up in the “Wikipedia Loop” because everything is so technical. Anyways I’m wondering these: - Who send the message? - What is a SAME header and how is a EAS message composed? - Who receives the message before us? - How do we receive the message? - What’s with the odd tone...
Technology
explainlikeimfive
{ "a_id": [ "e4xdsnx", "e4xeyri" ], "text": [ "> who sends the message? The united states gvmt requires all communications (radio, TV) companies to be connected to the government and capable of transmitting the EAS signal. > what is a SAME header? A SAME header is a standard way for the EAS system to ...
[ "url" ]
[ "url" ]
9ar1yl
why do cell phones' internet work outside or in the car but not laptops'?
Technology
explainlikeimfive
{ "a_id": [ "e4xeo90", "e4xem03" ], "text": [ "Cell phones use a data connection through cell towers, while laptops use wifi that needs to connect to a wireless router connected to the internet via an ISP (Comcast, etc.).", "Different transmitter/receivers. You can get a usb adapter for a laptop t...
[ "url" ]
[ "url" ]
9au923
Why did in the past using the phone disconnect you from the internet? How did we get past this problem today?
Technology
explainlikeimfive
{ "a_id": [ "e4y58h8", "e4y58r8", "e4y5i7n" ], "text": [ "Today we know phones as personal appliances. But before they were, phones were household appliances. A single line for one or more phones in a house to share. It was over this phone line that people first started getting on the Internet, us...
[ "url" ]
[ "url" ]
9aum21
How air conditioning and refrigerators cool the air.
I've been thinking about this too much recently. So normally to cool something you need something else that is already at a low temperature. So how does air conditioning and refrigerators cool air without ice or anything cold to begin with?
Technology
explainlikeimfive
{ "a_id": [ "e4y831l", "e4yc1ik" ], "text": [ "Basically it takes all the heat and throws it out of the room/refrigerator. This is why a refrigerator is warm on the back, as this is where the heat comes out. Same with the air conditions, The absence of heat results in cold.", "Ever used a can of c...
[ "url" ]
[ "url" ]
9avd31
Why movies are shown in < 60 FPS
Technology
explainlikeimfive
{ "a_id": [ "e4ye9rf" ], "text": [ "Customer preferences typically go to a lower framerate with slightly blurred motion, although nobody has really tested higher framerate films in a widespread commercial setting for a long time." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
9awt2k
What parts of a computer language make it "best" for this or that situation?
Technology
explainlikeimfive
{ "a_id": [ "e4yp41v", "e4yp70m" ], "text": [ "There are always tradeoff between ease of use and expressivity. If you want to be able to do more specialized things, you need more buttons in your craft. But then it's harder to use it. There are also problems with compatibility in different OS (looking ...
[ "url" ]
[ "url" ]
9axyil
How does a computer understand code?
Technology
explainlikeimfive
{ "a_id": [ "e4yvgfw", "e4yvcuc" ], "text": [ "**TL;DR A program called a compiler translates the code into machine code, which the computer is hardwired to understand.** The computer doesn't understand code. It understands machine code - instructions that are encoded in binary - because it is hardwir...
[ "url" ]
[ "url" ]
9azjyq
How does a computer cooler works and why shouldn't I just leave my computer open and point a fan at it?
Sorry for the dumb question, I'm genuinely curious about that. One of my extra coolers stopped working so I've been doing this instead, afraid my computer would overheat. I've been using a software to keep track of the inside temperature of my computer and everything usually stays within the 20-40 °C range.
Technology
explainlikeimfive
{ "a_id": [ "e4z6qwe", "e4z6sam", "e4z6vlv" ], "text": [ "This is technically ok (as long as all your temperatures are good, which you are monitoring). Just be careful about dust. With the way your computer is now, it is extra prone to building up dust, which would act as an insulator, causing ove...
[ "url" ]
[ "url" ]
9b147r
How do spammers get and circulate my cell phone number?
Technology
explainlikeimfive
{ "a_id": [ "e4zjefx" ], "text": [ "There are different ways, one example is they call random phone numbers, and if one picks up it gets added to the system as a valid phone number. They can also use leaks, and dumps, lots of websites get hacked and don't encrypt your phone number. Also a lot of people pu...
[ "url" ]
[ "url" ]
9b1hw0
Why are some electrical plugs so huge that they cover the outlets next to them? What is taking up all that space?
Technology
explainlikeimfive
{ "a_id": [ "e4zsbek", "e4znr40", "e4zmwku" ], "text": [ "The large component is the transformer. Household voltage can easily be stepped down to a few volts. However smaller the transformer, the lower the amps. If you look at all those power adapters around your house, you will see 2 numbers: vol...
[ "url" ]
[ "url" ]
9b1j9k
There were several search engines in use before Google came around (AskJeeves, etc). What made Google the ultimate game changer?
Technology
explainlikeimfive
{ "a_id": [ "e4zq2vj", "e4zn81h", "e4zn760", "e4zt0tp" ], "text": [ "Google was a search engine unlike any other that had come before. Way back in the day, search engines like Yahoo were actually more like the yellow page listings. They had a series of categories and categories within categori...
[ "url" ]
[ "url" ]
9b1l40
If gaming consoles are basically computers, why do game developers have to develop games for PC *and* consoles? And why can't a PS4 run PS3 and PS2 games?
Technology
explainlikeimfive
{ "a_id": [ "e4znm1j", "e4zne85" ], "text": [ "Video game consumers consoles are computers however they are not PCs. They have a very niche set or hardware and are designed in a way do that game developers can get a lot of performance out of relatively modest hardware because they know EXACTLY what th...
[ "url" ]
[ "url" ]
9b1pua
Why do old songs have a crackling sound?
& #x200B;
Technology
explainlikeimfive
{ "a_id": [ "e4zoedu" ], "text": [ "When songs were recorded on vinyl records occasionally damage to the physical medium would introduce crackling noises when played by a record player. The older the record, the more damage it incurred, unless carefully protected by the owner." ], "score": [ 5 ]...
[ "url" ]
[ "url" ]
9b9mql
What prevents the creators of an encryption method to decrypt any encrypted data?
Technology
explainlikeimfive
{ "a_id": [ "e51b55w" ], "text": [ "The methods used for most if not all commonly accepted encryption algorithms are publicly known. The good ones are designed in such a way that knowing the method used is irrelevant if you don't know the encryption key or password either set by the user or automatically ...
[ "url" ]
[ "url" ]
9ba4mk
how do cellphone carriers limit video streaming to a certain quality for example 480p
Technology
explainlikeimfive
{ "a_id": [ "e51ig1x", "e530ix1" ], "text": [ "They don't, your app/browser/plug-in is monitoring your bandwidth and scaling down when necessary. For those with an option to lock in a high resolution, you will have to wait through the lag while it buffers.", "It's actually more to do with the play...
[ "url" ]
[ "url" ]
9balln
How can solar panels turn light rays into electricity ?
Technology
explainlikeimfive
{ "a_id": [ "e51j8dy" ], "text": [ "The material in the solar panels has a somewhat tenuous relationship with its own electrons. When \"mr right\" (frequency) photon comes along it can bump those electrons right out of their current state, allowing them to go off and indulge that nomadic lifestyle they of...
[ "url" ]
[ "url" ]
9bbcpa
How do highway police speed traps work?
Technology
explainlikeimfive
{ "a_id": [ "e51r1mc" ], "text": [ "The radar guns that they use are decent at picking up discrete signals, so it'll be able to give to separate readings when two cars pass by. They also typically won't chase down every little violation, and if the trap is well-hidden they won't have to; instead, they'll ...
[ "url" ]
[ "url" ]
9bdhd2
How does defogging the windshield work?
I feel dumb for this, but I never know what temperature to put the air to. Also why doesn’t it help when I turn the AC off but still have the fan blowing air from outside at the window? Shouldn’t that equalize it?? Edit: RIP my inbox. Thank you for so many answers. Please do not share more Mark Rober links there are li...
Technology
explainlikeimfive
{ "a_id": [ "e52as65", "e52778n", "e52osym", "e52r6k1", "e52ab4d", "e5279zm", "e52uzzt", "e52sdao", "e52gogx" ], "text": [ "Think of air as a sponge. However the temperature of the air determines the size of that sponge and how much liquid it can hold. The colder it is, the...
[ "url" ]
[ "url" ]
9bgpdp
How are replay scenes in sports video games made?
Technology
explainlikeimfive
{ "a_id": [ "e5318ur" ], "text": [ "There's multiple ways of going about this. Most just save the game state each physics step, or just save the differences between the previous and next physics step (delta). This would effectively be almost like a video recording. Some games (like Starcraft) instead save...
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9bjvhp
Why is the US medical industry still heavily reliant on fax machines despite Obamacare initiatives to digitize records?
Technology
explainlikeimfive
{ "a_id": [ "e53h7on", "e53n88p" ], "text": [ "I have been told by doctor offices that the fax is secure, but email is not. The medical world is very concerned with patient privacy, almost to a fault, and it seems only a fax cannot be intercepted.", "There are well established, decades-old procedu...
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9bk48f
How do computers display graphics?
Technology
explainlikeimfive
{ "a_id": [ "e53lf5i" ], "text": [ "Imagine 9 people sitting in a 3x3 square. They each have a black or white sign that they can hold up depending on what I tell them to do. I would be the graphics card in this example and they would be individual pixels. In a grid like this 1-2-3 4-5-6 7-8-9 So I tell ce...
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9bm0ig
How does a treadmill calculates the amount of calories burnt when we run on it?
Technology
explainlikeimfive
{ "a_id": [ "e53yyvq", "e5405wj" ], "text": [ "It does some basic math based on the distance you ran, the speed, and your weight. Its not like it's actually measuring anything. Numbers could be wildly off.", "Calories are just a unit of measurement for energy. Because if that, a treadmill can calc...
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9bnqz6
How does a random number generator randomly generate numbers?
Technology
explainlikeimfive
{ "a_id": [ "e54duch", "e54dovd", "e54e240" ], "text": [ "So, I'm not getting into logic gates for an eli5. But the basics are to apply some math based formula to a seed. For example, a super simple one would be to ask the person for a number, then calculate the nth diget of pi, with n being the n...
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9bovbr
How does file compression work?
Technology
explainlikeimfive
{ "a_id": [ "e54m4my", "e54m34y", "e54lvkd" ], "text": [ "Imagine that you had a picture, and you chopped it up into tiny squares much smaller than a postage stamp. Then you assigned each one a color number between 0 and 255. Then you had to write down the color numbers, in order, on a piece of pa...
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9bs14o
When NASA say the Rover Opportunity will "automatically initiate recovery procedures", what does that mean?
URL_0 Im guessing it would have some tasks like start heaters, send out blips to Earth, etc? Is there any sort of listing available that shows the tasks?
Technology
explainlikeimfive
{ "a_id": [ "e55aiyz", "e55nm5l", "e55csqc", "e55jban", "e55nhpz", "e55mk4k" ], "text": [ "It's in sleep mode to conserve energy due to the storm. Now that the weather is clear, the battery will start charging up and it's getting out of sleep mode, meaning starting up all systems, perf...
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[ "url" ]
9bsfuc
Why do OS’s need to restart after an update?
Technology
explainlikeimfive
{ "a_id": [ "e55crqp", "e55q8zf", "e55pv1t" ], "text": [ "Because it massively reduces the potential for the update going wrong. The update is actually not installed until the restart. Then, the OS can go through a well-defined process where it it knows exactly what happens in what order and there...
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9bt7ry
Why are complicated passwords better than long passwords?
Technology
explainlikeimfive
{ "a_id": [ "e55hx0m" ], "text": [ "They aren't. A password 10-20 characters long with special characters and capitalization takes less time to \"hack\" than a simple 50 character long phrase. & #x200B; Edit: to add a bit more, the reason for this being is a computer \"guessing\" your password all day lon...
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9bw3uo
Why are more toilet flushes not like the water-conserving ones that they have on airlines?
Technology
explainlikeimfive
{ "a_id": [ "e565myb", "e565wwt" ], "text": [ "Its expensive to replace a system that works, and most of the water if not all is cleaned and goes back into the water cycle as vapour.", "toilets on aircraft, trains, and rv’s, flush waste directly into a holding tank which then must be pumped out an...
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9byukd
what do they do to cars when you get an oil change?
Technology
explainlikeimfive
{ "a_id": [ "e56rhga" ], "text": [ "Lift your car up, unscrew the oil drain bolt from the bottom of the motor, let your old oil drain into an oil pan, put a little bit of new oil in and let that drain to get any residual old oil out, put the drain bolt back on, fill your engine with new oil." ], "scor...
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9bzyrk
Why super High Definition Televisions just make everything look like a soap opera.
Technology
explainlikeimfive
{ "a_id": [ "e571jt2", "e57293y" ], "text": [ "I think you're taking about the motion smoothing feature. I turn that off in the menu first thing. It just feels weird. TV is supposed to be 60 frames per second and movies are supposed to be 24.", "This is a large controversy among people who are awa...
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9c0db7
How does a mobile phone call reach the other party? What happens after the signal reaches the cell phone tower?
Technology
explainlikeimfive
{ "a_id": [ "e575u3t" ], "text": [ "So, for mobile phones, any time they are on, they \"register\" with the network by connecting to a tower and authenticating, and they periodically keep in communication, even if they're not sending/receiving calls or data. When this happens, obviously the local controll...
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9c56mc
What are the advantages and disadvantages of software forking, and the legalities of it with regard to licenses and other issues?
Technology
explainlikeimfive
{ "a_id": [ "e583jqt" ], "text": [ "In code management of software projects \"forking\" is used primarily for _divergent_ development paths with the same original codebase, whereas \"branching\" is used for _convergent_ development. The difference here is that at the time the decision is made to \"fork\" ...
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9c69k9
- How does remastering work? If the source material produces a blurry film 25 years ago, how do they make it clear now?
Technology
explainlikeimfive
{ "a_id": [ "e58b3i7" ], "text": [ "So film is actually very high resolution. Like, the actual material that movie cameras record on. If they can go back to those original high quality sources and then use modern technology to process them, they can get better results because modern tech can preserve more...
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9c8njt
Why do people host torrents, and what benefits do they get.
Technology
explainlikeimfive
{ "a_id": [ "e58vmra" ], "text": [ "Many people host torrents because they feel like they should give back when they get something. It's an honor system and torrents just don't work if no one seeds them. There have been (and maybe still are, I haven't paid attention to it in a while) trackers which requir...
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9c9m45
How does your phone automatically know which police station to call when dialing 911?
How do cellphones and telephones (past and present) direct emergency phone calls to the nearest police station?
Technology
explainlikeimfive
{ "a_id": [ "e5939no", "e593bht", "e593a2x", "e59b1wa" ], "text": [ "Your phone doesn't know that at all. It just notifies the phone company that an emergency call is needed. The phone company knows the approximate location of every phone, and automatically chooses the assigned emergency call ...
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9cb7le
What does a CPU basically do?
I tried searching it up online but they use too complicated words or maybe I'm just dumb to understand what they mean.
Technology
explainlikeimfive
{ "a_id": [ "e59el90" ], "text": [ "A CPU is basically a calculator with a bit of memory. It adds numbers, multiplies numbers, etc then stores the result. Unlike a calculator, it reads in a series of instructions from memory rather than the user having to physically press buttons to tell it what to do. Al...
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9cd9ck
Ya know those ‘in utero’ pictures? Not ultrasounds or 3D, but the actual pictures of babies floating around that they put in baby books. How do they get those?
Technology
explainlikeimfive
{ "a_id": [ "e59thnb", "e59tywk" ], "text": [ "Rather than taking one ultrasound, they took lots of ultrasounds and used a computer to turn that into a 3D model of what it looked like inside the womb. [National Geographic did this with a dolphin, a dog, and an elephant back in 2006]( URL_0 )", "In...
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9ce9fl
How does cell shading work?
Technology
explainlikeimfive
{ "a_id": [ "e5agger" ], "text": [ "Cell shading uses fewer steps (gradations) from bright to dark - giving white highlights and black shadows a sharp and clearly defined outline. (Think 3 shades instead of 3,000.) When a computer renders a 3D scene, it simply decides on a limit in order to decide where t...
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9cfdj2
Why Windows still slows down after some time, and it's not fixed even when reinstalled.
Technology
explainlikeimfive
{ "a_id": [ "e5ab48n" ], "text": [ "Reinstalling WILL fix a Windows installation that has slowed down after some time. If it doesn't, then you're not reinstalling properly. Note that in this case, reinstalling means that you back up your data, wipe the PC's hard disk, reinstall Windows, reinstall all your...
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9cfngo
ms dos games
Technology
explainlikeimfive
{ "a_id": [ "e5acfes" ], "text": [ "Graphics and textures are done the same in every game, regardless of what it is going through. The game accesses the video driver (really the video register in the older games) and basically takes over drawing the screen. Like that it can produce graphics beyond what ba...
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9cfqkj
How do blogs, clickbait, and"fake news" sites actually make money from ads?
Technology
explainlikeimfive
{ "a_id": [ "e5acp73" ], "text": [ "There are three kinds of ad revenue. The first is as you suggest. It's called affiliate marketing, and they get paid when you click a link and buy something. That's actually fairly lucrative, as people who do end up clicking almost always buy something. The second is pa...
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9cgpey
How is Google Maps doing all this crazy 3D stuff?
Technology
explainlikeimfive
{ "a_id": [ "e5ak3wy" ], "text": [ "Most likely a combo between flyover mapping, satellite imagery and manual vector art done by designers" ], "score": [ 3 ], "text_urls": [ [] ] }
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9cgq51
How do transition lenses on glasses work?
Technology
explainlikeimfive
{ "a_id": [ "e5attry" ], "text": [ "According to [Transition's website]( URL_0 ), the lenses contain photochromic molecules, which react to UV light and darken the lenses. The sun gives off UV light. Although some UV light (or UV radiation) is blocked by the ozone layer, UV-A and some UV-B radiation passe...
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9ckbxs
How to stop getting ads of things you ve talked about but havent actually search for it?
Technology
explainlikeimfive
{ "a_id": [ "e5ba95c" ], "text": [ "Boy oh boy do I have a podcast for you! [ URL_0 ]( URL_0 ) & #x200B; This basically explains what is going on in terms of Facebook ads, but the same principles apply everywhere. It's a really complicated question to answer here and that podcast is about 30 mins and will...
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9clpz1
How can people have heart transplants without dying during the procedure?
Technology
explainlikeimfive
{ "a_id": [ "e5bivhr" ], "text": [ "A [cardiopulmonary bypass]( URL_0 ) is performed, connecting the patient to a machine that pumps and aerates blood in a sufficiently similar way to how the heart and lungs does it to keep their body mostly functional for the time the surgery takes. If one isn't availabl...
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9cmn77
What is "geo-redundancy" when it comes to cloud back up?
A specific cloud service was recommended to me with the caveat "if you don't mind geo-redundancy." Can anyone explain geo-redundancy in the context of back-up cloud storage. Cryptomator was the product being recommended. And no, I don't want to *just* use iCloud/OneDrive/Google Drive.
Technology
explainlikeimfive
{ "a_id": [ "e5bpxoy", "e5bpusn" ], "text": [ "Normal redundancy would be two or more computers that are capable of performing the task. Redundancy protects you against hardware failures in the computer that would take them offline Geo-redundancy is computers in two or more far apart locations that ar...
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9cpd3m
How do USB wall adapters convert large voltages in such a small cube?
Technology
explainlikeimfive
{ "a_id": [ "e5cc4uo", "e5cdad7" ], "text": [ "This becomes a far more interesting problem when factoring in the fact that the wall output is AC and we need DC for USB. Alternating current is what is found in our wall outlets, the electricity goes back and forth really fast in a pattern like a sine wa...
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9crha1
when telephone communication was in its infancy and they ran wires to connect all the telephones, how did they connect overseas calls?
Technology
explainlikeimfive
{ "a_id": [ "e5crkro", "e5crcbz", "e5crruu" ], "text": [ "In the earliest days, transatlantic communication over the phone was done via radio tower (and later microwave towers). They could have laid a cable, but the distance was too long for the technology at the time to give the voice signal enou...
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9cwn48
Public-key cryptography
How does the public-private key system work? Why does it work?
Technology
explainlikeimfive
{ "a_id": [ "e5dr2fm", "e5dq2hx", "e5dplq4" ], "text": [ "ELI5 example how public-key cryptography works: Imagine persons A and B want to transfer secret message but they can only send packages to each other in mail which is unsecure. Anyone can steal a package and take what ever contents are insi...
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9cz0gf
How does a home central AC work? Does it use any water?
The more I google about how a central air conditioner works, the more confused I get. I read that legionella bacteria is a concern with big air conditioning units, but only ACs that use a humidifier or cooling tower. I think just any ACs that use water can harbor the bacteria. I read that it’s a concern especially in l...
Technology
explainlikeimfive
{ "a_id": [ "e5e9qrf", "e5e7pa2" ], "text": [ "First, lets talk legionella. This is a water borne bacteria that can cause some serious health issues. Fortunately, as you saw, it's not a concern for small scale air conditioning. Home ACs use a refrigerant (Freon used to be it, R410 i believe is the cur...
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9d1k3b
Why does TV (usually) come through so clean and consistently while streaming on wifi tends to cut out and buffer more often?
Half the time I watch baseball on TV, other times I stream it. The TV feed is so consistent and smooth, but sometimes the internet cuts out and I have to reload the page. I understand the general gist of why this happens, but a thorough explanation would be appreciated!
Technology
explainlikeimfive
{ "a_id": [ "e5ervdo", "e5f70ve", "e5eu78f" ], "text": [ "Television and internet streaming videos are entirely different forms of transmission. TV signals are just broadcast and sent everywhere at once, no matter if you're watching it or not. Streamed videos are like any other thing you do on the...
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9d3hsz
how the rewind feature in things such as the snes classic or retroarch is possible and actually works
Technology
explainlikeimfive
{ "a_id": [ "e5f5rm8" ], "text": [ "SNES emulators are able to write out a \"save state\" which is basically a file that contains everything the SNES was doing at any given point in time, including a full copy of system memory, any hardware flags, and so on. This allows you to immediately restore the emul...
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9d3vtc
Why do solar panels stop working?
According to a recent BBC article, after 30 years or so solar panels are end-of-life and the scrap is no good for anything but landfill. What stops them working? What makes the scrap unusable?
Technology
explainlikeimfive
{ "a_id": [ "e5f81t4", "e5f9mdl", "e5fd49c" ], "text": [ "The panels on the voyager space probes worked for longer than 30 years. Higher tier panels in residential solar degrade at half percent a year and should still be at 90% of their output at year 20. Even if that curve is off a bit, that's st...
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9d5nh1
how my phone recognizes when I'm taking steps and accurately counts them
Technology
explainlikeimfive
{ "a_id": [ "e5flubt", "e5fg93r", "e5fg8ul", "e5fkzzu", "e5fn4qc", "e5fr07n" ], "text": [ "The Accelerometer in your phone detects the slight fall and stop that occurs each time you step down. It counts each time this happens as your steps. The phone also uses location services when av...
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9d6ee6
What are presidential alerts on the phone designed for?
Technology
explainlikeimfive
{ "a_id": [ "e5fliyt" ], "text": [ "> Is it for imminent nuclear strikes? Apocalyptic meteors rapidly approaching Earth? Yes, basically. Maximum level threats that every civilian **must** be aware of. It's there so that you know disabling disaster alerts does not disable presidential alerts." ], "scor...
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9d7kap
What would happen if I was to stay in the first gear of my car way past the speed it could handle ?
Technology
explainlikeimfive
{ "a_id": [ "e5ft18c", "e5fzdjs", "e5ft0b8", "e5fszrx", "e5ft6ar", "e5ft39x", "e5g0k4i" ], "text": [ "The valves controlling fuel and gasses going in and out wouldn't be able to close in time and burning fuel would shoot out through them, causing them to get caked in soot (and seve...
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9d9hlf
What do a dark room for photography do to the photos.
Technology
explainlikeimfive
{ "a_id": [ "e5g758n" ], "text": [ "Photographs taken with film camera use photographic film, special paper coated with chemicals that are sensitive to light. Their brief exposure to light focused through the lens of the camera allows them to record the image, but then they must be chemically treated to r...
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9d9oai
A technician is coming to our house next week to increase our internet speed. If our internet is already set up and we aren’t changing providers, why can’t the company do this instantly and remotely?
Technology
explainlikeimfive
{ "a_id": [ "e5g87xz", "e5g880a" ], "text": [ "Often they can. If they have to send a technician, it's because either (A) you need a faster modem, or (B) the physical wire coming into your house isn't good enough, or (C) the line approaching your house is shared with another building and needs to be s...
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9dbdap
why do videos generally play in 30 or 60 fps and not any number in between like 43fps
Technology
explainlikeimfive
{ "a_id": [ "e5gl0pu" ], "text": [ "60 Hz was the standard adopted for North American AC power delivery. This later translated into the standard frequency for television refresh for analog television. Which even later translated into the refresh rate for the LCD monitors used today. As to 30 vs. 60, both ...
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9dbkp1
Movies in space
Technology
explainlikeimfive
{ "a_id": [ "e5glz9x", "e5gmd8k", "e5gn4oh" ], "text": [ "It's real. Centrifugal force can simulate gravity for anyone on the inside of a spinning ring. If the ring is real big it doesn't have to spin particularly fast. And bigger is better, because the apparent gravity decreases towards the cente...
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9dckhn
How do computers play Chess? Is it a near infinite web of decisions that each have a probability of success associated to them?
Technology
explainlikeimfive
{ "a_id": [ "e5gt87i", "e5guge4" ], "text": [ "There are a lot of possible games, yes, but there are only a finite number. Further, there's only a finite number of legal moves that can be made at any given time. Computers will follow a set of moves and the possible counter moves, analyzing both the va...
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9dcuru
What’s all this stuff about DDR4, GDDR5 stuff on graphics cards? Is there a compatibility thing with them and motherboards or something?
Technology
explainlikeimfive
{ "a_id": [ "e5gvlt0", "e5guvku" ], "text": [ "DDR4 is regular RAM. You find it in consumer desktops/laptops. GDDR4 and GDDR5 are special high-performance RAM only used for graphics cards. They are soldered directly to the circuit board and cannot be replaced or upgraded. Ignore the similarity in name...
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9dfiu4
How are LED lights so bright and use so little energy?
Technology
explainlikeimfive
{ "a_id": [ "e5hcpg2", "e5hjsm4", "e5hedlk" ], "text": [ "Traditional light bulbs produce light through incandescence, which is when a material releases light energy when heated. They are inefficient because much more of the electrical energy that goes into the bulb is dissipated as heat than ligh...
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9dfjvg
How are blacklights made and how do they differ from normal lights?
Technology
explainlikeimfive
{ "a_id": [ "e5hd1n6" ], "text": [ "Blacklights simply put out UV (Ultra Violet) light, a wavelength that is not visible to the human eye. Blacklights often out out purple light as an indicator that they are active, and possibly as a bi-product of shining in that range." ], "score": [ 11 ], "t...
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