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bkyrt7
What is the Iron Dome, what does it do, and how does it work?
Technology
explainlikeimfive
{ "a_id": [ "emkb2vz", "emkbpk2" ], "text": [ "Its an anti missile system. It uses radar to sense and track incoming missiles and then fires a missile at that missile to destroy it before it hits its target.", "It's like a mosquito net. It doesn't show mosquitos inside. You're protected by a net w...
[ "url" ]
[ "url" ]
bl0t8k
Open vs Closed system?
I know that open systems can interact with other systems and closed does the opposite, but what does that really mean? Can you please give me an example. Thanks! Edit: In terms of computer systems (Information System Structure)
Technology
explainlikeimfive
{ "a_id": [ "emkqep6" ], "text": [ "**Open system:** Windows can be installed on pretty much any hardware, third party developers can make modifications to it (e.g., by making a computer game that runs on Windows), and Windows can interact with other types of operating systems (e.g., MacOS). **Closed syst...
[ "url" ]
[ "url" ]
bl16yf
Why smartphones don't have paper white screens so you can see them better in the sun?
Technology
explainlikeimfive
{ "a_id": [ "emks15z", "emkzuxv" ], "text": [ "Paperwhite is a type of electronic ink screen that uses tiny magnetized balls to show pixels on the display. For reading, it is perfect. Text and black and white images display with a decent resolution and minimal issue, but it's next to worthless for vid...
[ "url" ]
[ "url" ]
bl55e2
How come some motion capture suits have white balls on them and others have a bunch of black-and-white circles?
Technology
explainlikeimfive
{ "a_id": [ "emm9y9o" ], "text": [ "Programmatically they are very similar. Circles are used, because a circle is a circle at any angle. Circles are easy to resolve in code, because each pixel just yields to the center based on pixel averaging. The top example looks to be creating an entire virtual enviro...
[ "url" ]
[ "url" ]
bla1od
- How are blockbuster movies kept off the internet before disc/digital download release?
You would think in this day and age a computer hooked up at a movie theater by a mischievous employee could easily rip or piggyback off of various display cables. What stops this from happening?
Technology
explainlikeimfive
{ "a_id": [ "emmso7h", "emmwbq6" ], "text": [ "Back when I was a pirate in the 2000's it wasn't uncommon for me to have a copy of a movie before opening day. There's always a leak. Back then I found them on Usenet.", "Well, they're not, but there are some techniques to try to prevent this. One is ...
[ "url" ]
[ "url" ]
bla51l
Why is power over ethernet possible?
Technology
explainlikeimfive
{ "a_id": [ "emmv50g" ], "text": [ "Two main ways: 1. Simply take advantage of unused wires and send power over then. Ethernet cables have 8 wires organized into 4 pairs. At 100 Mbps, 2 pairs are unused. At 1 Gbps though, all 4 pairs are in use, so another method is needed. 2. Ethernet uses differential s...
[ "url" ]
[ "url" ]
blqg45
What's the difference between a Samsung "fast charging" plug and a standard iPhone one? Is there any science to it or is Samsung just trying to shoehorn my money into their pockets by limiting the amount of power its consuming?
Title says it, I have to lug around this bulky plug anywhere I want to have my phone charge faster than 22 hours for a full charge, while my girlfriend can plug her iPhone into pretty much any usb. Is there science behind it? Because it seems like the power source is the same.
Technology
explainlikeimfive
{ "a_id": [ "emqi4zr" ], "text": [ "The power sources are not necessarily the same. Yes, they'll all provide 5V over the USB connection, but phone chargers are often limited to 1 Amp of current \"draw\" and tablet chargers/\"fast\" chargers will allow current and voltatges above the USB specification. The...
[ "url" ]
[ "url" ]
blrkef
How can a secure wireless (or other) connection be established when the initial communication to establish it is not secure?
My basic understanding is this: two devices initiate communication, and agree on a secret code to keep others from listening in on their conversation. What's to stop everyone else from listening in while the secret code is established, allowing everyone to understand it? What am I missing here?
Technology
explainlikeimfive
{ "a_id": [ "emqrs82" ], "text": [ "Before we established a huge public key infrastructure, a protocol called the [Diffie-Hellman key exchange protocol]( URL_0 )was created which enables two parties to generate and secretly share a private key over a public channel which can be used to encrypt future comm...
[ "url" ]
[ "url" ]
blrryb
Why does sometimes a youtube video buffers in the middle forever and I have to reload the page and skip to that part to have it work?
Technology
explainlikeimfive
{ "a_id": [ "emqt4a0", "emrbl1t" ], "text": [ "You are queued up waiting for something that isn't arriving. It's like being in the slow lane at the grocery store and deciding to jump to another checkout lane.", "Your adblocker could be blocking an ad that is supposed to show up at that point among...
[ "url" ]
[ "url" ]
blsplu
Even before colonialism, why were European and Asian countries typically more advanced than African?
We hear all the time of European and Asian history with their technological advancements, is there any reason why these didn't happen on the African continent? I'm talking about pre 1800 Europe dividing up Africa and conquering and destroying everything.
Technology
explainlikeimfive
{ "a_id": [ "emr8wxh", "emr26qa", "emr66w3", "emr29ml", "emr2ail" ], "text": [ "ELI5: Answer, your question is incorrect. History didn't happen that way. & #x200B; ELI20 Answer: So lets go over a few things. & #x200B; Pre-1500 West Africa was more advanced than Western Europe. The reason w...
[ "url" ]
[ "url" ]
blsqjs
Why do some PC screens appear to inverse colors on the screen depending on the viewers angle?
For example, looking at a Lenovo Thinkpad from an angle about 45 degrees from parallel to the screen makes the image appear inverse without colors.
Technology
explainlikeimfive
{ "a_id": [ "emr4xfr", "emr41lk" ], "text": [ "This is caused mostly by the TN LCD's, or Twisted Nematic. These LCD's are cheap and energy efficient, but suffer from poor viewing angles due to way that it bends light through different filters to achieve different colors, or to block light. When you vi...
[ "url" ]
[ "url" ]
blt4r1
how does a heads up display, display the image sort of not as a reflection but far back floating in the air?
Class presentation soon and this is still black magic to me.
Technology
explainlikeimfive
{ "a_id": [ "emrdxpb" ], "text": [ "I think the comments so far are missing what you are asking. HUDs are unique in that the imagery appears to be floating further out in front of you than a reflection like what you'd see in a car window. Mitary HUDs (and those red dot sights you see on some weapons) use ...
[ "url" ]
[ "url" ]
blt7tt
How are old recordings converted to new formats?
Once a song/video has been recorded and stored using particular technology, when a new form of storage develops, how is the content recreated into the new format? For instance, music in the 80s was stored in cassette tapes, then CD, then digitally (I might have missed a lot of steps). How would a recording on tape be t...
Technology
explainlikeimfive
{ "a_id": [ "emrmf72" ], "text": [ "The studio mix down and mastering was recorded to a high quality format. In the past this was analogue tape. ie 2\" reel to reel tape This was then duplicated to the delivery medium. Ideally, when going to a newer delivery format, they go back to the highest quality ver...
[ "url" ]
[ "url" ]
blu5wv
How do thief's use skimmed credit cards in person?
I recently had my credit card skimmed for the second time. While working it out with the bank, it was found that the skimmer used it in person rather than order things online. Given that I still have my credit card, how did he/she actually use my card in a store? Do they make their own cards or something?
Technology
explainlikeimfive
{ "a_id": [ "emrf1y4", "emrfeed" ], "text": [ "You can use a mag strip reader/encoder. They're dirt cheap and easy to get. The person who used it probably wasn't the same person who actually stole your numbers. Thankfully merchants see fraud as a cost of doing business and are pretty good about gettin...
[ "url" ]
[ "url" ]
blvw1e
Why does Google Chrome need so much RAM to operate?
Technology
explainlikeimfive
{ "a_id": [ "emrtspr", "emrzzs0" ], "text": [ "It doesn't. It only seems to consume an inordinate amount of memory because it uses memory if it's available. If you have 2 computers with the exact same specs except for the RAM and loaded the same websites chrome will use more memory on the system with ...
[ "url" ]
[ "url" ]
blzym0
How do heart surgeons keep patients' blood pumping during surgery?
Like let's say a patient is getting a heart transplant How do they keep blood pumping through the body while the hearts are getting switched-out? Or even like a normal heart surgery like a coronary bypass. Do they meddle with the heart while it's still beating?
Technology
explainlikeimfive
{ "a_id": [ "emspd6g", "emsvn58" ], "text": [ "There’s a special machine that pumps blood in place of the heart. It has to be set up with tubes placed in specific locations in the heart or major blood vessels. There’s a person called [a perfusionist]( URL_0 ) whose entire job is to run and monitor thi...
[ "url" ]
[ "url" ]
bm2d6k
Why do gloves, as an example, not work with the touchscreen on my smartphone, but a banana peel does?
Never quite understood this.
Technology
explainlikeimfive
{ "a_id": [ "emt85ae", "emtahdl", "emtf0gu" ], "text": [ "The banana can conduct electricity as it contains water, the glove can’t. That’s why some gloves have little bits of wire woven into the tips of the fingers to allow electricity to flow.", "Capacitive touch screens work by your finger s...
[ "url" ]
[ "url" ]
bm4upg
Why does a brand new computer go form lightning fast processing to the eventual slow and sluggish processing?
When you get a new computer, phone, or tablet, everything is fast. It boots up fast, it opens apps quickly, and programs run flawlessly. Eventually, the computer start having “hiccups” and slow downs, and after a few years it takes your OS a few minutes to boot up. If the computer is not bloated with software, viruses,...
Technology
explainlikeimfive
{ "a_id": [ "emts85w", "emu9bea", "emtq7x6" ], "text": [ "> If the computer is not bloated with software, viruses, and is otherwise “clean”, what exactly is breaking down in the hardware or software? Nothing, computers don't \"slow down\". Not even hard drives to any appreciable degree. Two things...
[ "url" ]
[ "url" ]
bm6wva
how do solar panels convert heat to electricity.
Technology
explainlikeimfive
{ "a_id": [ "emu9ckf", "emu9qro" ], "text": [ "They don't convert heat to electricity, they convert light to electricity, and they do so by the [photoelectric effect]( URL_0 ). Basically, when a photon with enough energy hits the right kind of atom, it can knock an electron loose, which can then be us...
[ "url" ]
[ "url" ]
bm8azh
Molten Salt Nuclear Reactors
How do they work, and on what principles?
Technology
explainlikeimfive
{ "a_id": [ "emuyvh0" ], "text": [ "Well, no one has answered yet... So I'll try to explain it: To put it simply. An MSR uses salt instead of water to transfer thermal energy. However, instead of having fuel rods like in traditional nuclear reactors, the uranium fuel is mixed in with the salt. This create...
[ "url" ]
[ "url" ]
bm9n9k
how would pilots operating from carriers in ww2 navigate at sea when there are no reference points?
Im thinking flying some 100-150 miles one way then getting into some crazy dogfight and then flying back while your own carrier might be changing position. I know some planes had dedicated radio/navigation guy but also planes with just pilot were used (like wildcat or japanese zero)
Technology
explainlikeimfive
{ "a_id": [ "emuw05v", "emv05ai", "emuypj6", "emv69f5" ], "text": [ "Everyone who was flying would have a magnetic compass, a watch, and navigational charts to let them figure out where they were. Regardless of if you had a navigational guy to do it for you or not, someone had to figure out th...
[ "url" ]
[ "url" ]
bmeel6
Why are main disks in our computer called C: by default and not A:?
Technology
explainlikeimfive
{ "a_id": [ "emvzfvw", "emvz198", "emvz1fv", "emwbhzq", "emvzivw", "emvz8r3", "emw4kyr", "emw8tkj" ], "text": [ "The a: and c: nomenclature come from IBM PC and MSDOS. In those early PC, there was one or two drives: floppy drives. They were the primary persistent memory. The fi...
[ "url" ]
[ "url" ]
bmetbe
Why can’t we just go back to using whatever materials we used before plastic?
Technology
explainlikeimfive
{ "a_id": [ "emw2jlw", "emw3kl6", "emwa5fk", "emw2myx" ], "text": [ "The cost, really. All of the infrastructure of a our modern society is based on making, molding or using plastic goods. To change it we'd need to readjust... like everything... Theres a reason that we switched to plastics- th...
[ "url" ]
[ "url" ]
bmf0kg
How does an air fryer works?
Technology
explainlikeimfive
{ "a_id": [ "emw7dln" ], "text": [ "An “air fryer” is just another name for a table top sized convection oven. Instead of immersing your food in hot oil, the fryer blasts your food with superheated air." ], "score": [ 15 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bmjcz4
What gives an auto-tuned voice that distinctive sound?
Technology
explainlikeimfive
{ "a_id": [ "emx8jex" ], "text": [ "Think of autotune as a hypothetic lane assist in a car: You're supposed to be in the right lane, but actually driving with one wheel in the left lane. Autotune will move your car to the right so you're perfectly centered. Now if you atually move towards the left lane, a...
[ "url" ]
[ "url" ]
bmjui8
Why people still buy iPhones even if Android phones are useable and cheap?
Technology
explainlikeimfive
{ "a_id": [ "emx377j" ], "text": [ "Lol you ready for this. You ain't ready for this. And I'll join by saying more users on reddit are android users." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bml08j
Why does Excel slow down as a process continues
Let's say I am autofilling 10,000 rows of 1000 columns (10mil cells), as I sometimes do. The first 1000 rows go very fast, the next 1000 a bit slower, the next slower... Each row is slower than the one before. Rows 9000-10,000 take longer than the first 5000 rows do.
Technology
explainlikeimfive
{ "a_id": [ "emxef1w", "emxhqf8" ], "text": [ "Software developer, & #x200B; Until we get a developer on the Excel team from Microsoft in here, it's hard to say precisely. What I do know is there's a scripting engine running on each cell, trying to detect formatting changes, or macros or expressions t...
[ "url" ]
[ "url" ]
bmlbjp
Why are most laptops with a 4K display touch-screen?
Technology
explainlikeimfive
{ "a_id": [ "emxg2aw", "emxgja1" ], "text": [ "Being 4k AND touchscreen is in no way related to each other technically. The feature of being 4k resolution is currently a \"premium\" feature. Most laptops that have this feature also have the \"premium\" feature of having a touchscreen. Think of buying ...
[ "url" ]
[ "url" ]
bmpwkl
Why do the videos from the early 1900's look like they are being played at 2.5x speed?
Technology
explainlikeimfive
{ "a_id": [ "emyp7kc", "emymch9" ], "text": [ "The original hand cranked cameras like the pathé and the bell & Howell 2709 had what was called an 8:1 gear ratio, which meant for every 360 degree crank it would produce 8 frames. There was a song that cameramen would sing as they handcranked, which woul...
[ "url" ]
[ "url" ]
bmuc82
How were maps made before the digital age?
Seems like an extraordinarily difficult concept that I can’t wrap my head around. How do they know what they’re drawing or how accurate their drawing is? It’s amazing that those old maps are even as accurate as they are. Cartographers are so cool.
Technology
explainlikeimfive
{ "a_id": [ "emzzrx2", "emzs3h6" ], "text": [ "[Surveying]( URL_2 ). - Take sticks with very carefully measured marks on them, and place them at various points. - Take a telescope-like optical instrument ([Theodolite]( URL_1 )) which can be adjusted vertically, horizontally, and also adjusted to focus...
[ "url" ]
[ "url" ]
bmxj0s
why is direct sunlight bad for electronics?
Technology
explainlikeimfive
{ "a_id": [ "en0g8sj", "en0ee7o" ], "text": [ "Direct sunlight is bad for pretty much everything and almost always for the same reason: UV radiation breaks down matter. In the case of electronics, they will break down the protective layers of the circuit boards and eventually start digging into the co...
[ "url" ]
[ "url" ]
bmy6t8
How do they clean dirty plastic / glasses etc. before recycling?
Technology
explainlikeimfive
{ "a_id": [ "en0kvcb" ], "text": [ "I think just melting them down into a molten glass burns off anything that would be on them" ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bmzeuw
Why is Google search web address so complicated? What's with all the complicated numbers and letters?
Technology
explainlikeimfive
{ "a_id": [ "en0wwfs" ], "text": [ "URLs can't have certain characters in them, like quotation marks and spaces. When a website needs to use a URL that uses these characters, it replaces them with special sequences of allowed characters in their place. IIRC a quotation mark, for example, is replaced by %2...
[ "url" ]
[ "url" ]
bn1uth
Why isn’t everything solar powered?
I was gifted a solar powered watch 5 years ago. Never had to worry about swapping watch batteries. After the first solar powered item was made, why didn’t every piece of technology, equipment, gadget etc become solar powered when it was invented? Why aren’t more things being made solar powered moving forward?
Technology
explainlikeimfive
{ "a_id": [ "en1jmdf" ], "text": [ "For large scale electronics solar power is nowhere near as efficient other sources of electricity." ], "score": [ 6 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bn2021
How a speed camera works on a multiple lane road?
Technology
explainlikeimfive
{ "a_id": [ "en2ly3w" ], "text": [ "Police cameras use radar guns to measure the speed of cars. Radar works be shooting radio waves at the target, and measuring the amount of shift caused by the Doppler effect on the radio waves to determine the speed of cars. The reason they work on multiple lane roads i...
[ "url" ]
[ "url" ]
bn62cj
Why is ethernet faster than WiFi?
At my school campus when I speed test with ethernet on school computers I get 100mb/s but when I connect via wifi on my phone or laptop, it's only about 3 mb/s?
Technology
explainlikeimfive
{ "a_id": [ "en2lwco", "en2o4dt", "en2ucnj" ], "text": [ "Imagine taking to a friend face-to-face; in a quiet room; seated across from each other at a table. Now imagine talking from around a corner, in a crowded hallway; during a house party. In the first scenario, you and your friend understand ...
[ "url" ]
[ "url" ]
bn6vjc
How did we code computer code and operating systems?
Technology
explainlikeimfive
{ "a_id": [ "en2uja0" ], "text": [ "Code is executed as binary machine instructions in memory. Ever since we stopped programming computers with wires, there has been a way to make a file, or a tape, or a ROM, or load core (Google \"core memory\"). Some ways were bad, manually transforming instructions to ...
[ "url" ]
[ "url" ]
bn73wt
if corn has no nutritional value, then how did culture's in South America/Mexico thrive because of it?
Technology
explainlikeimfive
{ "a_id": [ "en2x50t" ], "text": [ "It is not the case that corn has no nutritional value. In 100 grams of corn, there is 18.7 grams of carbohydrates, 1.35 grams of fat and 3.27 grams of protein, and a good quantity of vitamins B1, B3, B5 and phosphorus. URL_0" ], "score": [ 3 ], "text_urls": ...
[ "url" ]
[ "url" ]
bn7tfx
What exactly is Data rot and why is storing electronic photos on a phone long term a bad idea?
Technology
explainlikeimfive
{ "a_id": [ "en39a7t" ], "text": [ "1. The storage media uses a physical process (electrical charge for a SSD, or magnetic moment on a HDD) to store the data. On the tiny physical scale that this happens at, external forces can over time disrupt the stored data. Atoms vibrating because they have heat, ext...
[ "url" ]
[ "url" ]
bn8ejp
How is helium collected/made and put into tanks?
Technology
explainlikeimfive
{ "a_id": [ "en3blyq", "en3bcwl" ], "text": [ "Helium is obtained through fractional distillation of natural gas. It occurs naturally in these deposits, so when the gas is extracted, the helium is separated out and stored. It's next to impossible to obtain it any other way.", "We can't produce hel...
[ "url" ]
[ "url" ]
bnbp05
How does the Internet work?
Technology
explainlikeimfive
{ "a_id": [ "en48fne" ], "text": [ "Your computer is connected to your modem. That modem is connected to whatever ISP distribution center that is in your city via cables. That Distribution center is connected to a bigger ISP with larger cables that connects different cities and regions together. That ISP ...
[ "url" ]
[ "url" ]
bnhlwp
Why can't phone screens be dimmed way more so that they are easier on our eyes when it's dark?
Technology
explainlikeimfive
{ "a_id": [ "en5p5wh" ], "text": [ "Do you have an iPhone? I can dim mine to where it’s hardy viewable even in darkness. Also, I saw a video not too long ago about a trick you can do to dim it even further." ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bnjqvf
How does noise cancelling work?
Technology
explainlikeimfive
{ "a_id": [ "en6b32m", "en6mxbc", "en6odq3", "en74smf", "en773gp" ], "text": [ "Active noise cancelling works by the headphones having a microphone on the outside that detects environmental noise, and then speakers on the inside that play the opposite soundwave to cancel it out. Sound trav...
[ "url" ]
[ "url" ]
bnjx1c
How do street lights know to turn colors when you pull up to an intersection?
Technology
explainlikeimfive
{ "a_id": [ "en6cfm7", "en6ca1g" ], "text": [ "There are sensors on the road. Have you ever seen [those circles covered in rubber?]( URL_0 ) Whenever you drive over them it let's the traffic light know there's a car there.", "There are two mechanics. 1 is magnetic sensors buried under the crosswal...
[ "url" ]
[ "url" ]
bnkcf9
How can online games like first person shooters be so in sync across all users without hardly any delay?
Technology
explainlikeimfive
{ "a_id": [ "en6gr63", "en6m1no", "en77g7n", "en73322", "en6m7c9" ], "text": [ "Fast internet and faster servers. Human reaction times are on the order of 100ms or so. Ping time, which is round-trip packet flight time is often on the order of half that or so. Round trip is therefore on the...
[ "url" ]
[ "url" ]
bnkmui
Do Wire Colors Matter?
Looking to build something and the guide for it contains color coded wires. Do I need to buy wires of various colors or are they all created equal?
Technology
explainlikeimfive
{ "a_id": [ "en6hucq", "en6iw9r", "en6l3bz", "en6hlcr", "en6hssh", "en6tb9d" ], "text": [ "In terms of electrical capacity , all colors of the same thickness are equal. But, there are expectations about what wire colors mean. Usually red or black is hot, white is neutral and green is E...
[ "url" ]
[ "url" ]
bnlurn
How do neural networks work?
Technology
explainlikeimfive
{ "a_id": [ "en75k1d" ], "text": [ "Highly recommend the YouTube series from 3brown1blue on this topic. Visual explanation of this will always be better than just text in an comment. URL_0" ], "score": [ 4 ], "text_urls": [ [ "https://youtu.be/aircAruvnKk" ] ] }
[ "url" ]
[ "url" ]
bnmrvp
Why didn't vector graphic become mainstream rather than raster/pixel?
This is not exactly a PNG vs EPS argument. I've been working as a designer since four years now and since I work in print, the pixel data available on the net doesn't help much. I find myself converting stuff to vectors a lot of time. Apart from photos, everything else that could be vectorized is converted in my work. ...
Technology
explainlikeimfive
{ "a_id": [ "en777me", "en74920" ], "text": [ "The hardware that will ultimately display or print your work is pixel-based. This means that any vector-based solution requires additional processing before it can be used. This can also mean additional storage/transmission costs. Consider a CGI animated ...
[ "url" ]
[ "url" ]
bno9f2
Why are magnets not a problem for electronic devices anymore?
I remember in the 90's/00's you were not supposed to get magnets near electronic devices. All devices also had warning stickers regarding magnets. Today it seems not to be an issue anymore. Many devices have built in magnets, for example to attach a keyboard, charger etc. What has changed that made devices less sensiti...
Technology
explainlikeimfive
{ "a_id": [ "en7rh3y" ], "text": [ "Two main reasons. 1. Before LCD displays there were Cathode Ray Tube (CRT) displays. These used magnets to direct an electron beam towards the phosphorescent screen to create the image. Having a magnet near the monitor could magnetise the display, altering the beam's pa...
[ "url" ]
[ "url" ]
bnqd7r
How do file compression work? Why can't we just infinitely compress a file inorder to make gb to kb?
Technology
explainlikeimfive
{ "a_id": [ "en87tcq", "en87tnz" ], "text": [ "Compression works a lot like shorthand. You make shortcuts and special “words” to represent certain sequences. As a super simple example, let’s say a file is 9 followed by 100 8’s. That file would be 101 bytes. But I could say any repeated sequence of num...
[ "url" ]
[ "url" ]
bnugig
How did people wake up on time before alarm clocks were invented?
Technology
explainlikeimfive
{ "a_id": [ "en98qu7", "en9aokj", "en98x87" ], "text": [ "There used to be Knocker-Uppers who would go around waking people up. URL_0", "Body clocks. From being a tradie for 5 years now I get up just before 6am for work. After doing that for a month my body just always wakes me up at around 5:...
[ "url" ]
[ "url" ]
bnz9zb
Why did my friend always have to turn on channel 3 in order to play Nintendo 64?
Technology
explainlikeimfive
{ "a_id": [ "enap3zo", "enaperr", "enap3qa" ], "text": [ "I'm assuming you mean that your friend had an older style television and he would switch to Ch 3 to get the N64 to work. Not every TV came with composite inputs (think your red, white, yellow cable) and only had RF tuners (the port you plug...
[ "url" ]
[ "url" ]
bo00o7
Torrents. Could studios sabotage them if they actually wanted to?
Technology
explainlikeimfive
{ "a_id": [ "enawphc", "enawdc3", "enavwlk" ], "text": [ "They do try to overload a torrent with clients that you can't really connect to. I forget the term for it, flooding maybe, but essentially it stops people from downloading or reduces speed to a crawl. They can also submit bad files to the m...
[ "url" ]
[ "url" ]
bo01o8
How does exposure allow a camera to see into space?
Whenever someone takes a photo of the sky and you can see stars and the galaxy, most people attribute it to a high or long enough exposure setting on their camera? How exactly does that work?
Technology
explainlikeimfive
{ "a_id": [ "enavxv3", "enaw0dy" ], "text": [ "The reason we can't see stuff on the night sky as well as we would like to is not that they're invisible, it's just that there's so little of their light reaching us that they're indistinguishable from the backdrop. Long exposure on camera sort of gathers...
[ "url" ]
[ "url" ]
bo0c4a
How come when you open task manager to close a slow program, the program will sometimes suddenly start working again as if nothing is wrong?
Technology
explainlikeimfive
{ "a_id": [ "enayxsv", "enazoiy" ], "text": [ "I hope someone who knows some in depth details on this can chime in, but the short version is: Opening the task manager by your standard ctrl+alt+delete is not like starting any other program. It's treated by Windows differently, and interrupts other func...
[ "url" ]
[ "url" ]
bo0zks
Why is a poor signal strength bad and how, specifically, does it affect my conenction?
Technology
explainlikeimfive
{ "a_id": [ "enb5igd", "enb6whd" ], "text": [ "Think of it like you're trying to get water into your glass from a reservoir through a series of pipes. Your signal being weak is like the pipes not being big enough to handle all the water so only a little bit gets through to you, making it take longer f...
[ "url" ]
[ "url" ]
bo2z0n
Why do PC's need fans or water cooling, and cell phones only need heat sinks?
There are games on mobile that seem to push phone limits hard. PC's do this, but have fan cooling or water cooling. How do cell phones play games like PUBG and Fortnite all the while just using heat sinks?
Technology
explainlikeimfive
{ "a_id": [ "enbpsyh", "enbs5cv", "enbo3wb" ], "text": [ "A cellphone running a game is running the game at settings that keep it within a certain thermal range, so you don't get a burnt hand, battery going pop, thermal shutdown etc & #x200B; It's quite possible to thrash a pc up to the point that...
[ "url" ]
[ "url" ]
bo57vs
Holding Batteries
How come when I hold a AA battery and place a finger on either end I don't complete the circuit and get a zap?
Technology
explainlikeimfive
{ "a_id": [ "enc92dp" ], "text": [ "You do complete the circuit, and you do get a \"zap.\" It's just that the voltage is so low (1.5 volts) and your skin has high enough resistance that there is very little current, a zap too small to notice." ], "score": [ 10 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bodmrm
Why can a 20 minute video take 5 minutes to upload onto YouTube and then the same video, take 40 minutes uploading to Google Drive?
Technology
explainlikeimfive
{ "a_id": [ "enf50xn", "enfl308" ], "text": [ "This is a good question, considering Youtube is a subsidiary of Google and all. I can't believe it has anything to do with server speeds, Google probably has the fastest servers in the whole world. I don't upload to Youtube often, but I have noticed uploa...
[ "url" ]
[ "url" ]
bohn24
How do password managers know your password without actually knowing your password?
Technology
explainlikeimfive
{ "a_id": [ "engmtfq", "engdz7t" ], "text": [ "Every single answer here is incorrect. They all explain how websites store passwords, not password managers. **PASSWORD MANAGERS DO NOT HASH PASSWORDS**. If they did, you will never be able to retrieve the passwords that you store in there. Instead, what ...
[ "url" ]
[ "url" ]
boht7i
What is a Processes Working Set?
Hello, working with Windows Powershell and i get with get-processes a WS value wich is the Working Set value. I have no clue what the value mean though... Can someone help me get that? thanks :)
Technology
explainlikeimfive
{ "a_id": [ "engglee" ], "text": [ "Think of it like $20 dollar bills in your pocket. Its a resource (pageable memory) that has been allocated and now quick and easy to use. If you run out, it’s gonna take some time/work to get it (hard page fault), kind of like doing another ATM transaction." ], "sco...
[ "url" ]
[ "url" ]
bol96r
why does putting "www" before the address matter for some sites but not others?
Technology
explainlikeimfive
{ "a_id": [ "enhqk61", "enhjbjp", "enhit19", "enhjyq7", "enhobc2" ], "text": [ "Originally, the world wide web was just a small part of the internet. The internet included the world wide web, but it also included FTP (file transfer protocol), e-mail (okay, we still have that), Usenet (bull...
[ "url" ]
[ "url" ]
bomxhb
How are hard drives/sd cards/digital storage nearly doubling in storage capacity, while remaining roughly the same size, year over year?
Technology
explainlikeimfive
{ "a_id": [ "eni4tq5" ], "text": [ "Digital storage capacity has nearly everything to do with storage *density*, or the number of bits that can be stored per unit area. Imagine you have 100 light bulbs, and they can be switched on and off individually via a set of switches you have. Each bulb represents a...
[ "url" ]
[ "url" ]
bool78
What are delegates and lambdas?
Technology
explainlikeimfive
{ "a_id": [ "enj2jau", "eniq4c0" ], "text": [ "I know this is ELI5 but I'm going to assume you have at least a tiny bit of programming knowledge. Literally day one stuff. A variable is a value with a name. For example: let MyVariable = 5 The name is `MyVariable` and the value is `5`. A function looks ...
[ "url" ]
[ "url" ]
boouix
How does captcha work exactly and what is it supposed to accomplish?
Technology
explainlikeimfive
{ "a_id": [ "eniuam0", "eniy8gg" ], "text": [ "Websites use captcha schemes to separate human users from simple computing users. Because humans can do some things easily while same task is harder on computer. At same time, new AI algorithms are solving what we're previously hard computing problems. As...
[ "url" ]
[ "url" ]
boqfuq
Why does 24 FPS look fine for films and television, but looks terrible for video games?
Technology
explainlikeimfive
{ "a_id": [ "enjdzv9", "enjrtf1", "enkjhjf", "enjxoin", "enkj0er" ], "text": [ "Movie frames are formed by a camera with an aperture being open for a period of time. This means there is “motion blur” as things move across the frame while the shutter is open. In contrast the computer is cal...
[ "url" ]
[ "url" ]
borni0
How does somebody take a video first person view, but when they look in a mirror, they don’t see the camera?
Technology
explainlikeimfive
{ "a_id": [ "enjtvre", "enju5b6" ], "text": [ "Can you explain what you mean or provide an example? Mirror shots are usually filmed at specific angles to hide the camera, use sets with duplicate rooms on either side of a false mirror, or digitally erase the mirror in post.", "I might not be the be...
[ "url" ]
[ "url" ]
bory6j
How come you can power a radio exclusively via radio waves and we still have to charge our cell phones?
When I was a boy I built a crystal radio that fit into a tic tac box. This thing had no battery and ran a tiny little earpiece. Plans for these are available all over the net, I genuinely want to know why we aren’t using cell phone antennas to passively harness RF and rectify and recycle. If it’s possible to listen to ...
Technology
explainlikeimfive
{ "a_id": [ "enjux98", "enjv4n7" ], "text": [ "Its a matter of scale. Your radio was able to function on just milliwatts of power, your phone has an ~11 Watt hour battery pack so if it lasts just 11 hours that means you're using about a watt of constant power. There just isn't enough random radio wave...
[ "url" ]
[ "url" ]
bosr09
Why can’t we text using bold, italics, or underlines?
Technology
explainlikeimfive
{ "a_id": [ "enk7jbi" ], "text": [ "The SMS service standard simply doesn’t allow for “markup” as, for example, HTML does for the web. It was invented at a time when phones only had numeric buttons. You could just start using a markup standard but it would be confusing for the many older phones that didn’...
[ "url" ]
[ "url" ]
boywfi
How do people uncover vulnerable mistakes in chips or software?
Hi, you often read about how cyber/computer security experts uncovered a new vulnerability in chips or computer software. I theory, I often understand how they work, but they seem so specific that I cant imagine how people identify them and learn about them. E.g the famous Spectre or Meltdown. How does the process of i...
Technology
explainlikeimfive
{ "a_id": [ "enmjgvg", "enn1zsq" ], "text": [ "There isn’t a set method to uncover vulnerabilities, people typically start with how they think something works. The guess could be right, or it could be wrong. Sometimes these implementations have side effects that either went unnoticed, or was decided t...
[ "url" ]
[ "url" ]
bozf6c
How Does Google Pixel's Image Processing Software Work?
I got a Google Pixel 3a last night and am blown away by the camera's processing capabilities, especially with the Night Sight mode. I took a picture of the city from my balcony and it was unreal watching the software do its thing and sharpen the image, bring out the colors, etc. It looks almost as good as a picture I t...
Technology
explainlikeimfive
{ "a_id": [ "ennvq2g" ], "text": [ "Here's a [blog by Google]( URL_1 ) that explains how Night Sight works specifically. And here's [a more in-depth article]( URL_0 ) that is less ELI5. In summary: If the phone is still, and the subject isn't moving, the camera just has a longer exposure. If the phone is ...
[ "url" ]
[ "url" ]
bozv3j
why is WPS insecure?
Apparently, Wi-Fi Protected Setup is so insecure that Android removed support in Android P, the reasoning being that a PIN is easily brute-forced. But in my understanding WPS is normally disabled, until you press the button on the router which gives you a window of a couple of minutes to pair your device. Unless you ha...
Technology
explainlikeimfive
{ "a_id": [ "enmunyd" ], "text": [ "the button doesn't turn WPS on, it turns on the broadcasting of the pin. you can brute force the pin whenever you want as long as WPS is enabled." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bp3bcf
How does voice recognition technology work? What do our phones, cars, Alexas, etc. do to allow them to hear and interpret what we say?
Technology
explainlikeimfive
{ "a_id": [ "enoivsy" ], "text": [ "What we perceive as \"sound\" is actually changes in air pressure. When something makes a sound, it causes vibrations in the air. These \"vibrations\" are made up of peaks (positive pressure) and troughs (negative pressure). Once the vibrations reach our ears, our ear d...
[ "url" ]
[ "url" ]
bp5d5x
How does a digital thermometer measure the temperature?
Technology
explainlikeimfive
{ "a_id": [ "enotmar", "enotd8n" ], "text": [ "There are a number of different types of electrical temperature sensor. One of the most common, robust and cheap is the thermistor which changes electrical resistance with temperature. That is used in a circuit which gives an output to drive the display d...
[ "url" ]
[ "url" ]
bp5w8r
Why isn’t possible for all cars to move in unison when a red light turns green instead of seeing a green light and having to wait a few seconds before you can move?
Technology
explainlikeimfive
{ "a_id": [ "enoyno1" ], "text": [ "It's to do with the spaces between the cars. At the lights there's only a small gap, and if all the cars started together then the gap wouldn't grow and if someone hits the breaks there would be an accident. By waiting a second for the car in front to move, you create a...
[ "url" ]
[ "url" ]
bp6jf5
How are computer parts manufactured to be so small?
This has genuinely confused me. How would you be able to manufacture something that is so small yet looks like it's so powerful?
Technology
explainlikeimfive
{ "a_id": [ "enpar0p" ], "text": [ "Very very carefully! To be more serious, the smallest things that are manufactured in volume are \"Integrated Circuits\" (ICs). For example, microprocessors or Graphics Processing Units (GPUs) can contain billions of tiny transistors on a piece of silicon the size of yo...
[ "url" ]
[ "url" ]
bp8dy8
How do websites know to go to the mobile version on your phone even when you click a desktop link but don't know how to go to the desktop version on your desktop if you click a mobile link?
Technology
explainlikeimfive
{ "a_id": [ "enq829g", "enqag4p", "enpxemn", "enpx8ez", "enr32mg" ], "text": [ "When you send a request for a website, you send information about your device and what exactly you are after in the headers of a request. There is a header called \"user-agent\" this basically defines what devi...
[ "url" ]
[ "url" ]
bp8m0j
. Is it possible to hack into a self driving car and change its destination or even reck it ?
Technology
explainlikeimfive
{ "a_id": [ "enq5mur", "enpxt6b" ], "text": [ "This is the very thing that some cybersecurity researchers at Georgia Tech are investigating and the answer appears to be \"Yes\". Although there haven't been any large scale attacks on them and self-driving cars themselves have not been deployed on any m...
[ "url" ]
[ "url" ]
bp9arp
why does wikipedia need millions of dollars each year? Isn't it just a couple of servers running an open source script?
Technology
explainlikeimfive
{ "a_id": [ "enq9a4g", "enq8xu3", "enqe90x", "enr95nx", "enqgh7k" ], "text": [ "First off the foundation receiving your donation is not Wikipedia, its Wikimedia, a larger parent organisation that operates a multitude of projects. The servers which run a site the size of Wikipedia are not t...
[ "url" ]
[ "url" ]
bp9as6
Why do video streaming websites like YouTube choose to support 60 FPS only for 720p and above?
Technology
explainlikeimfive
{ "a_id": [ "enqa6nx" ], "text": [ "The lower quality tiers are usually for people who have slow internet connection. 60fps would however need more data to be transferred so it'd be counter-intuitive to make the 480p and lower available with 60fps." ], "score": [ 4 ], "text_urls": [ [] ]...
[ "url" ]
[ "url" ]
bpa7jx
how does the WhatsApp exploit bypass the sandbox restrictions by the OS
Technology
explainlikeimfive
{ "a_id": [ "enqmj2g", "enqvrm4" ], "text": [ "\"A buffer overflow occurs when a programming error allows more data to be written to a given area of memory than can actually be stored there,\" Rik Ferguson, the vice president of security research at the security-software firm Trend Micro, told Busines...
[ "url" ]
[ "url" ]
bpew27
Why did the look of movies get "clearer" in the 1990s?
Technology
explainlikeimfive
{ "a_id": [ "ensgfcm", "enshuc5" ], "text": [ "The quality of film has evolved over time. We've learned to make film that doesn't crush black as much. Early black and white movies don't look nearly as good as later black and white movies. The color process has evolved too, allowing far more nuanced sh...
[ "url" ]
[ "url" ]
bpj1st
How do printers work so accurately and fast?
Technology
explainlikeimfive
{ "a_id": [ "entxog0" ], "text": [ "I don’t know what exactly you are looking for as an answer... They work accurately because the motor that controls the printing head works in very small increments (typically 96 positions per inch) and the ink injectors can inject extremely small quantities of ink. They...
[ "url" ]
[ "url" ]
bpkslw
How did humans all over come to know what parts of a plant are edible, toxic, and which ones serve as remedies for illnesses ?
Technology
explainlikeimfive
{ "a_id": [ "enudfmb", "enus00k", "envbcgs" ], "text": [ "Trial and error, and they were often wrong. Many traditional plant remedies are total nonsense, or even actively harmful, and tomatoes were widely thought to be poison by most of Europe for hundreds of years.", "Humans didn’t just appea...
[ "url" ]
[ "url" ]
bpmcx1
Why do TV remote batteries last a lot longer than wireless video game controller batteries?
Even when the controller sits idle while I watch Netflix, the battery life is substantially less than a TV remote.
Technology
explainlikeimfive
{ "a_id": [ "enuy9pz", "enx8zcx", "env9e3d" ], "text": [ "You’re not constantly pushing all of the buttons on a tv remote for hours on end. Simply moving left on a joystick would constitute as always sending a signal. ...and that’s not even getting into controllers that vibrate.", "TV remotes ...
[ "url" ]
[ "url" ]
bppjlx
how can lightbulbs change color?
Technology
explainlikeimfive
{ "a_id": [ "enw3a0a" ], "text": [ "The light source consists different color \"channels\". A controller can make combinations of these channels, leading to different colors. Similar to mixing paint to create more colors!" ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
bpqu7x
How do cameras at golfing events keep track of a golf ball after it's been hit when its moving so fast and so small?
Technology
explainlikeimfive
{ "a_id": [ "enwitok", "enwtmyo", "enx0sp4", "enwnb3f" ], "text": [ "Typically they change the contrast in their viewfinder so the sky is white and the ball is black. That, and years of practice.", "Now imagine doing it with cameras that used tubes to capture in SD resolution. Props to the...
[ "url" ]
[ "url" ]
bptgki
How was ice produced in the days before freezers in warmer climates? Was there any way to conserve foods/meats?
Technology
explainlikeimfive
{ "a_id": [ "enx78rn", "enx7t59", "enx8zam", "enx723c", "enx764t" ], "text": [ "Ice was \"harvested\" from cold lakes, wrapped in insulated crates, and shipped to distant locations to keep food fresh in an \"icebox\".", "salt was the main way meat would be stored so like salted pork. d...
[ "url" ]
[ "url" ]
bpw2m7
why does the airport security make us take our electronic devices out of our bag during security scan?
Technology
explainlikeimfive
{ "a_id": [ "eny3cez" ], "text": [ "Large screen devices like laptops or tablets will just look like blank squares on the x-ray scanner. So they won't be able to see if you're hiding something underneath it or not in your bag. Same reason why they make you take out *everything* from your pockets, even cig...
[ "url" ]
[ "url" ]
bpzlwt
Why does NASA have to wait until 2024 to land on the moon?
Why can’t we start that mission today? Don’t we have the knowledge from the Apollo missions to get us there?
Technology
explainlikeimfive
{ "a_id": [ "enzbm1f", "enzbwus", "enzaqhe", "enzd8s2" ], "text": [ "We don't have any sort of rocket that can travel to the moon and back. We don't have a vehicle that can detach from that rocket and land on the moon. Takes a LOT of time and money to design and build those. Even 2024 seems wa...
[ "url" ]
[ "url" ]
bpznw0
Why do some devices and programs need to be rebooted/restarted when a new setting or update is applied to them?
Technology
explainlikeimfive
{ "a_id": [ "enzcdjs" ], "text": [ "If your operating system is like a running car, it would be dangerous to replace parts while the car is running. So you shut the car off. Replace the parts, then start it up again. Basically when your computer starts, it has a chance to replace files and do other things...
[ "url" ]
[ "url" ]
bq2hp1
How did old hand-drawn animation achieve such consistent color?
Mainly wondering how they avoided discoloration or the presence of brushstrokes. Thanks!
Technology
explainlikeimfive
{ "a_id": [ "eo0ksl0", "eo1h8wv", "eo0pas6", "eo1j3or", "eo1yes8", "eo1d9w6", "eo1dcfh", "eo248ns", "eo1ngsq", "eo2tq5e", "eo3bjdv", "eo2m66r" ], "text": [ "Speed and skill. Each pencil drawing by an animator was traced in ink on to a transparent sheet. Once the...
[ "url" ]
[ "url" ]
bq3lm2
why do diesel motors have a much more “heavy duty” sound than regular gas motors?
Technology
explainlikeimfive
{ "a_id": [ "eo0tosf", "eo13hto", "eo13ih7" ], "text": [ "Diesel engines have no spark plug. Compression alone causes diesel fuel to ignite. As a result the compression needed in a diesel engine is much higher than a gasoline engine. To handle the nigh pressure inside the engine they must be made ...
[ "url" ]
[ "url" ]
bq4ohb
Why are laptop cameras are still so consistently low quality even though it's 2019?
Phone cameras despite having size constraints are always getting better every model. Even tablet cameras are still far superior than laptop cameras
Technology
explainlikeimfive
{ "a_id": [ "eo15cpx", "eo1lh04", "eo1n8b6" ], "text": [ "I'm no expert, far from it, but I'll hazard a guess that it's about cost to produce vs the use and saleability of the product. A laptop camera is generally only used for video calling, so you don't need image stabilization, HDR or 27 bazill...
[ "url" ]
[ "url" ]
bqahi6
NASA's permanent moon base; how will they handle the lower gravity?
I saw NASA's video about wanting to have a permanent moon base by 2024, but this made me wonder: How do we get around the lower gravity? People who work at this lunar base for years will eventually run into issues with their muscles and bones. Transporting people back and forth all the time to avoid this seems it would...
Technology
explainlikeimfive
{ "a_id": [ "eo2lpln", "eo2mcnv" ], "text": [ "Well, Moon gravity is better than ISS gravity (= no gravity). On the ISS there have been many experiments that have found things that limit the damage from no gravity, and a one-year stay is common. No doubt, more would be needed on a Moon base. The whole...
[ "url" ]
[ "url" ]
bqdg1j
How do objects get the same amount of power from one port as it would from an extension cable that splits said port in 3 or 4, wouldn't it just cut the power in half or in quarters giving less power to the object?
Technology
explainlikeimfive
{ "a_id": [ "eo3j9or", "eo3o5yc" ], "text": [ "Most things don't use the entire amount of current that a breaker can deliver. Don't think of the power from an outlet like it's a set amount... The amount of power being delivered from the outlet depends on how much power is required by the things plugge...
[ "url" ]
[ "url" ]
bqf89e
why usual purchases with a card need something memorable (PIN code), but online purchases have their secret code printed right on the card?
The way I understand, the usual (non-contactless) payment is a prime example of 2FA: you present your card, and then either sign or enter PIN code. First option ticks something you have (card) + something you are (the person who can white a signature matching the card's one), second - something you have (card) + someth...
Technology
explainlikeimfive
{ "a_id": [ "eo40m6p" ], "text": [ "This is something that is changing in the EU. They are going to add in 2 factor authentication for cards. For example one of the cards I have requires me to unlock my banking app using my pin or fingerprint and approve the transaction. Effectively requiring someone to s...
[ "url" ]
[ "url" ]
bqfkxo
how is this 'climbing a flat videoscreen' effect achieved?
Watching the Eurovision last night made me think of this entry from 2016 by Russia. Great song and the staging was fantastic. But can I hell figure out the 'climbing the wall' bit from about 1:40 in - it's a flat screen isn't it? But it can't be! Then what turns at 2:00? The screen? A second screen? A projection? Drivi...
Technology
explainlikeimfive
{ "a_id": [ "eo42hq7", "eo46uf4" ], "text": [ "The white wall isn't actually flat, there are platforms that poke out for him to stand on. Its been painted white in such a way as to appear as flat as possible to a camera or a distant viewer, and you'll notice they only do camera shots that face straigh...
[ "url" ]
[ "url" ]
bqgg1e
Why is it that the first 10-20% of most IPhone battery’s are used up within the first 20-30 minutes while the last percent can sometimes last up to 15-20 minutes?
Technology
explainlikeimfive
{ "a_id": [ "eo4m5pn" ], "text": [ "Two things are happening. First, it is not easy to tell how charged a battery is. The only thing you can really tell from a battery is the voltage. From that, and previous study of the battery, software in the phone and the battery can estimate the remaining charge. Sec...
[ "url" ]
[ "url" ]
bqgmqt
How are soda cans recycled when they have a plastic film inside them?
Technology
explainlikeimfive
{ "a_id": [ "eo4c3on" ], "text": [ "There are dozens of YouTube videos about that, but the basic process involves melting everything down and separating the aluminum from the not-aluminum. A technical term for undesirable matter in melting and smelting is *dross*." ], "score": [ 3 ], "text_url...
[ "url" ]
[ "url" ]