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h9kfks
|
Why do some countries still struggle to make nuclear weapons?
|
We hear pretty often than Iran is attempting to enrich uranium and make nuclear weapons. The same has been said of some other countries and there are countless other nations that would like nuclear weapons but can’t make them. How is this the case when this is 80 year old technology at this point? If we could make them in 1940, shouldn’t even technologically behind the times countries be able to make their own now? Was 1940 America really more scientifically capable than large African or middle eastern countries are today?
|
Technology
|
explainlikeimfive
|
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"It’s not a matter of scientific difficulty, the process is well known and you can look it up online. The difficulty is mostly in procuring the materials and equipment against the will of the international community. You need enriched uranium and a large number of centrifuges to refine it to weapons-grade, but these aren’t easy to come by. When your geopolitical enemies embargo these items and dispatch spies to disrupt the process, you’re forced to procure equipment through other unsavory channels and try to do this work in secret. Iran has a lot of very powerful enemies and very few friends, and they can’t just go buy nuclear weapons equipment.",
"Because it's incredibly hard. You need to enrich uranium, which requires you to make and handle a highly toxic, corrosive gas that eats just about anything except nickel, and send it through hundreds of high-speed centrifuges that are spinning so fast that even the extra weight of a single screw on one side can rip them apart. Or you could build dozens of electromagnetic apparatus the size of houses to enrich a few milligrams at a time. Either way, it will take a LOT of electricity; someone's going to notice. Then you need a way to extract the metal from the gas, form it into a precise shape, and you've got your core. In order to make it fission, you're going to need to machine at least two superpure explosives with sub-millimeter accuracy into a series of explosive lenses, which all have to be set of at exactly the same time; normal detonators won't work. You need something like an explosive bridgewire detonator, and those are neither cheap nor easy to get. It's not that any of the tech is hard to understand. It's just that a lot of it is very expensive, and the international community keeps an eye on this sort of thing.",
"You are not giving 1940’s USA enough credit. The Manhattan Project was a massive government controlled undertaking. It forcibly brought together the brightest physicists the allies had access to and provided them with all the support and backing that was possible at the time. Yes, the underlying technology is indeed 40 years old, but this isn’t the kind of technology that is published, or readily accessible for reverse engineering. Still, you are correct in that it is much easier to build a nuclear weapon in 2020 than it was in 1945. One of the major problems preventing every country from having their own nuclear weapons is obtaining the materials in order to construct one. If using uranium, it must be isotpicially enriched before it is “weapons grade.” This process is very arduous, and the facilities to do this are large and expensive. If using plutonium, the plutonium has to be created in a nuclear reactor. Again, the facility to do this is large, expensive, difficult to construct, and not easy to hide. Now that there is no longer a negotiated deal to keep them from doing this Iran could have a weapon in a couple years.",
"Check out [Countdown to Zero Day]( URL_0 ) to read more about Stuxnet and how Iran’s nuclear weapons program was countered.",
"It's not the technology, its the materials and the specialized tools and equipment that is the hard part. There are many international treaties and laws against exporting these needed items.",
"Assembling a Little Boy gun-type atomic bomb isn't exceptionally difficult Acquiring the highly enriched uranium for the core, and designing a compact weapon that you can actually deliver to your enemies is the hard part. Access to the centrifuges that are capable of refining uranium is controlled and anyone with a site for refining uranium is checked to see if their centrifuges are setup to make a lot of low grade stuff or a little bit of high grade stuff, you have to run several centrifuges in a row to get weapons grade uranium. As for delivery, early atomic bombs were absolutely massive. Little Boy weighed 4,400 kg and only had a yield of 15 kT. 4,400 kg is a really heavy warhead and very difficult to launch on anything short of an actual space rocket like the Falcon 9, or requires a heavy bomber to deploy. A modern US W80 warhead has a yield of 5-150 kT and weighs just 130 kg which means you can launch it on a much smaller and easier to hide/deploy missile. They can make the bombs, but they can't make the bombs they need"
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[
"url"
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[
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h9kvnf
|
What are Cybernetics?
|
Something in my brain just isn't clicking. The wikipedia article is difficult for me to understand, and maybe I'm just having one of those days.
|
Technology
|
explainlikeimfive
|
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"Cybernetics can be a lot, a plethora of different categories and systems can fall under the umbrella of cybernetics. A very simple understanding is: machine experiences > machine computes > machine reorganizes > machine repeats The goal of cybernetics, no matter what it is applied to, is to create the most efficient system possible."
],
"score": [
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
h9nepv
|
how does platforms like Steam or Amazon know if you're using a correct visa card or not if you didn't buy anything with it?
|
Technology
|
explainlikeimfive
|
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"text": [
"There is some internal logic to the format the numbers should be in. So in many cases a typo of one digit would make the number invalid. Old computer games could also do that offline where the CD key had to follow a certain format and rules. Someone else can probably explain in detail how the check actually works.",
"The last digit is a checksum: for any given combination of the first 15 digits, there's only one possible value for the last digit of the card. The website can perform that same calculation to verify that you didn't make a mistake entering in the card number.",
"There is a method called the [Luhn algorithm]( URL_0 ) that can be used to check the digits of the card number. The last couple digits of the card number are the result of the Luhn algorithm on the other digits. This is built in as a simple check for errors.",
"Credit Card numbers are generated with something called the Luhn algorithm. It is a checksum algorithm. It takes the 15 real digits of your credit card and determines the 16th. This means that only one final digit is valid, and 9 are invalid. If you type a number in wrong, it will definitely fail the checksum. The algorithm also counts every second digit differently (they're doubled). This means that simply swapping digits also causes a failure, which is the most common type of error when typing a card number."
],
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16,
6,
6,
3
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[
"url"
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[
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|
h9vjqc
|
How do undercurrent inputs damage devices?
|
Technology
|
explainlikeimfive
|
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"I'm used to low Voltage/ low power devices (microcontrollers and sensor circuits) and under current doesn't damage the equipment for me; it just doesn't work. I can forsee some circuits having issues with under *voltage* on input, resulting is current flowing in the wrong direction which can cause damage to polarized devices (such as diodes). For high power electronics (like city power) I'd have to defer to someone else"
],
"score": [
5
],
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[
"url"
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[
"url"
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|
h9weai
|
How does a breathalyzer tell how drunk you are
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Your body takes time to process alchohol, and a typical healthy adult male's liver can break down roughly 1 \"standard drink\" in about an hour. If you take a shot, for example, the alcohol in that shot is gradually carried in the blood and shunted into your liver for breakdown by specialized enzymes until no more of it is floating around. While alcohol is in the blood, it gets around; anywhere that it might be excreted -- even in small amounts -- might see some bit of it released. The lungs are packed with very small blood vessels that normally help take in oxygen from your breath and release carbon dioxide from respiration. When ethanol (the alcohol we drink) is freely hanging around in the blood, some of it gets into those small vessels in the lungs and manages to make it out with the carbon dioxide-laden air when you exhale. By taking a sample of that breath and bringing into the presence of certain chemicals, one can figure out roughly how much of the blood's volume is comprised of ethanol. This is what a breathalyzer does -- you breathe into the device, which is built to send your breath to a waiting set of reactive chemicals whose reactions with ethanol are well-understood. Depending on how vigorously they react, the device can give an estimate of how much of your blood volume is ethanol versus other things. The percentage a breathalyzer displays are that number: the estimated proportion of your blood that is ethanol, rather than other typical contents. This is a useful marker for gauging intoxication, as most people who do not have other medical problems or drink chroncially will fall within typical ranges for the correlation between blood alcohol content and motor/cognitive effects of intoxication. Breathalyzers do vary in terms of sensitivity and consistency. Smaller, less-sophisticated units such as the field breathalyzers used by police during traffic stops (or a variety of home devices freely purchasable on the internet), are less precise and consistent than the more-sophisticated tabletop units usually used (at least in the US) for secondary BAC screening after arrests (and even those may not be quite as reliable as one would hope, depending on how well-maintained they are). Breathalyzers in general are categorically inferior to testing a blood sample taken during intoxication -- rather than relying on breath measures that introduce a variety of possible errors into the estimated measure of BAC, blood samples can be used to more directly ascertain the proportion of alcohol in rhe blood."
],
"score": [
8
],
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[
"url"
] |
[
"url"
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|
h9wp9q
|
How did people construct wells before modern drilling and how dangerous was it?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"It depends on how deep the water table is, but... they just dug a hole until they reached the water table. There's always some risk, but it's probably not as dangerous as you think There are actually some really interesting 'primitive building' channels on YT that have men digging wells as part of their builds and it's neat to watch. Edit to include a video link since reddit didn't want a reply to my reply for some reason: [ URL_0 ]( URL_0 )",
"They dug it by hand, using wood or bricks to prevent the sides from collapsing inwards. It was a very dangerous job. They still use this method in some parts of the world. These days concrete rings are often used. You lay a concrete ring on the ground, stand in the middle and dig away all the ground under it. Once it has dropped down you put another concrete ring on the top and repeat until you hit water."
],
"score": [
27,
3
],
"text_urls": [
[
"https://www.youtube.com/watch?v=jh1pgMjIP2g"
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[]
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|
[
"url"
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[
"url"
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|
h9y5l2
|
Why does Google need users to agree to a Terms and Conditions to sign up for a Google account but don’t need it to perform a Google search when a search could expose even more personal information?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Google doesn't send you a cookie if all you do is go to the URL_0 search page so it doesn't need a GDPR popup. Google doesn't need you to agree to its non-cookie data tracking. It just needs to make a statement on its data tracking available (which it is by clicking on the privacy link in the bottom of the Google search page). You have no ownership interest in Google's data on you. You can request that they delete that data, but where that is available its because you have a statutory right (IE, your government says that Google needs to make that option available to you). If all you're doing is using Google's search then you have a very simple, risk free relationship with Google. However, absent some contractual provision you *do* have an ownership interest in your Google account. That significantly complicates the relationship between you and Google. What if Google wants to terminate your account? Or scan your emails for targeted advertising? Absent some contractual provision it can't do either of things, at least not easily. Or lets take a worst case scenario for Google: what if you're using Google Drive and a glitch causes all of your data to be deleted? Well absent some contractual provision the default position between you and Google is that you owned that data and Google is responsible for its replacement. If it can't replace it then Google owes you money for its loss. How much it owes you is up to a judge or, worse, a jury. And Google doesn't even know where that judge or jury is. It could potentially be liable wherever it is that you live, and Google's users live in just about every country on Earth. Does Google want to subject itself to a corrupt judge in Kazakhstan because it accidentally lost the dick pics you were saving on Google drive? Probably not. What this is all to say is that as soon as you make a Google account the relationship between you and Google becomes incredibly complex with a lot of unknowns for both you and Google. The way that Google gets rid of those unknowns and limits its liability to you is by having you agree to its terms, in which you expressly agree that you have no property interest in your account or anything on it, that Google can terminate that account for any reason at any time, and that if you want to sue Google over a dispute involving your account you have to do so in one of a handful of locations where Google operates.",
"Because lawmaking and the internet have a very toxic relationship. The internet moves at such a fast rate while laws and regulations move so slow. Regulations will always be playing catch up with the internet and there will constantly be loopholes and hypocrisy. Also... old people run the government."
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6,
4
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|
ha11j9
|
why does fast charging in mobile phones charge the phone to a certain % very quickly and then significantly slows down?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fuzyutc"
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"text": [
"Think of it as blowing up a balloon. At the early stages, you can inflate it pretty fast because there is not as much pressure. As the balloon expands and the pressure inside gets higher, it gets harder and harder to blow into it."
],
"score": [
16
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[
"url"
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[
"url"
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|
ha2k6g
|
How does a color-changing light actually do that? For example: DualShock's light bar
|
Technology
|
explainlikeimfive
|
{
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"fv05iex"
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"text": [
"Multiple different-colored LEDs inside, dimming to different brightness. Color mixing does the rest. It's the same concept that computer screens use for their pixels, they're also just 3 monochrome (red, green, blue) subpixels at different brightness to make one \"colored\" pixel."
],
"score": [
6
],
"text_urls": [
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[
"url"
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[
"url"
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|
ha41jy
|
- Why do older movies/shows/news/recordings have a much different "tone" of voice and feel to them? Like if you watch old movies like "It's a Wonderful Life" or hear any of Kennedy/FDR's speeches, it sounds so different than the voices on tv today?
|
Sorry for the awful explanation... Edit: Thank you everyone for the detailed and thorough explanations!
|
Technology
|
explainlikeimfive
|
{
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"text": [
"The Mid-Atlantic accent, or Transatlantic accent, is a purposefully-cultivated accent of English that blends together the most prestigious features of American and British English (specifically Received Pronunciation for the latter). Adopted in the early 20th century mostly by American aristocrats and Hollywood actors, it is not a native or regional accent; instead, according to voice and drama professor Dudley Knight, it is an affected set of speech patterns \"whose chief quality was that no Americans actually spoke it unless educated to do so\". Primarily fashionable in the first half of the 20th century, the accent was embraced in private independent preparatory schools, especially by members of the Northeastern upper class, as well as in schools for film and stage acting. The accent's overall use sharply declined following the Second World War. It was popularly used in movies, television, etc. as a \"non-accent,\" meaning something in any English-speaking country could readily understand but not tie directly to a specific place.",
"My 2c... Early movies followed the tone of stage plays, as this is what early movie actors were trained in and this is the tone the audience expected and understood. Stage actors need to speak loudly and clearly, as there was little or no audio setup. They had no microphones, there were no speakers. Just loud, clear actors. There are also no close-ups in stage plays. Actors had to exaggerate their reactions to make it clear what the character felt. Over time, the tone of movies evolved. Acting generally became more natural. Actors no longer had to shout to the back of the theater, instead they had to act as real people would behave in real situations. Actors reactions became minimal. The camera did the work. & #x200B; I'd like to think old movie audiences would have a hard time understanding a modern movie. Sudden scene changes, unnatural camera angles, actors in the far distance being heard clearly. It may seem very artificial to them.",
"Also noteworthy. In europe most tv's used PAL standard. which runs at 25 frames per second. Americans used a 30 Frames per second standard (NTSC) As a result a lot of american series were sped up by 4% when displayed in europe. Which gave a slight but notable higher pitch to voices. (could be adjusted in processing, but often wasn't )",
"There were a couple of accents that were considered acceptable/mainstream, and pretty much anyone who was on film/tv/radio used those - in the US, the main one was a \"Mid-Atlantic\" accent (a blend of received pronunciation and New England \"upper crust\" speech patterns), while in the UK, the standard was received pronunciation. Over time, there's been more acceptance of regional dialects/accents, but the \"generic\" accent for American film has shifted to much more of a Californian accent (perhaps with slightly crisper enunciation than the average person uses day-to-day)."
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75,
17,
4,
3
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ha530h
|
How Does Water (or other fluids) Ruin Electronics?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Water conducts electricity. Allowing current to flow between components unmetered and unchecked leading to short circuiting. Also corrosion",
"Water is conductive if it has some minerals in it, but you need to go out of your way to get water without minerals. Most electronics use different voltage levels. Some components get to hot and get destroyed when they have the wrong voltage applied."
],
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6,
4
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[
"url"
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[
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|
ha5h2p
|
The difference between 32-bit and 64-bit.
|
Technology
|
explainlikeimfive
|
{
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"text": [
"imagine you're adding numbers like in school where you write 1 3 5 3 1 6 0 5 1 2 5 6 _________ 1 8 6 5 7 2 That's how a computer adds numbers too. A computer with \"more bits\" can work with longer numbers at once. But more importantly, because it \"knows bigger numbers\" it can use more storage: Every tiny bit of storage has an address. The processor shouts the address like a cook in a restaurant kitchen, then the storage with that address gives whatever it had stored. More storage-addresses is like a Gordon Ramsay who can shout at 64 instead of just 32 different cooks to get him lamb sauce. The storage/cooks still work the same speed each, but a *Rordon Gamsay* who can handle 32 at a time get's half as much lamb sauce as Gordon 64-bit Ramsay.",
"Here's an explanation which doesn't use any strange analogies: The number refers to how many bits there are in special storage locations called registers, which is where the CPU stores the data it's working on right at this instant. As other posters have said, more bits means you can store bigger numbers in those registers, but being able to do arithmetic very, very quickly on 64-bit numbers instead of 32-bit numbers isn't why computer makers made the jump. The reason is because CPUs use the data in registers to get data out of memory, so the bigger your registers are, the more memory your system can use. How much memory are we talking about here? Well, 32-bit numbers top out at 4 GB of RAM. You can only uniquely number something above four billion different objects if you only have 32 bits to work with. Four billion may sound like a lot, but 4 GB is kind of a constraining amount of RAM, even on desktops, these days. With 64 bits, you can uniquely number over [18 quintillion]( URL_0 )\\* different objects, so that's the limit of 64-bit addressing. We likely won't hit that for a while yet. \\*(I linked to the right thing. Read the article for the *unsigned* value, and realize that x86-64 isn't the whole world.)"
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26,
6
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[
"url"
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[
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|
ha8f0x
|
Why does undervolting a CPU not decrease the performance?
|
How does undervolting a CPU keep the same performance? I feel like it makes sense that it would cause a decrease in performance since it consumes less power right?
|
Technology
|
explainlikeimfive
|
{
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"fv180de"
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"text": [
"Assuming you don't touch the clock speed, the processor is still doing the same tasks at the same rate. Although reducing the voltage too much will eventually bring it to a point where the processor starts returning the wrong values to operations, which tends to lead to some quick system crashes"
],
"score": [
5
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[
"url"
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[
"url"
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ha95nw
|
Why does an electric device trip the breaker when it jams?
|
When I'm mowing my lawn with my electric mower, and it gets clogged up (because I've gone too long between mowing), why does it trip my breaker? I mean, I can understand the mower jamming up and stopping (like it does). But is there some sort of electrical feedback that goes back into my house? Why is the breaker affected at all, by something that happens in my backyard? This also happened when I was using an electric saw to cut wood, and the saw jammed in the wood (although in that case it tripped the breaker in the extension cord, and not the house).
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Electric motors are just a big spool of wire, in general we would consider hooking hot to neutral with just a wire to be a short circuit or a very very large heater, but in general it'd be a bad idea. But motors are built to spin within a magnetic field, this creates a voltage that pushes back (Back EMF) and reduces the current that flows through that wire far below what the resistance of the wire would limit it to When the motor stops (stalls) its no longer spinning and generating this reverse voltage, its now just a very low value resistor connecting hot to neutral which results in a huge amount of current flowing that will trip the breaker. When stopped AC motors are really high powered cylindrical toasters, but when running they pull 1/100th or 1/1000th the stall current.",
"An electric motor takes a certain amount of current to generate a certain amount of torque (power/force). When the motor is stuck, it will immediately draw as much current as the circuit let's it, also known as the stall current (correct me if I'm wrong about that name) . The motor sees it as something really heavy is pushing against it, and it pushes back equally hard. But this takes a lot of current, which trips your breaker. Side note, even really small motors can have an obscene stall current. Hobby helicopter motors can draw over 30 amps each at stall."
],
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13,
6
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[
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[
"url"
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ha9hl1
|
With all of the scams out there, how has the DHS not found a way to track phone numbers and nail scammers by now?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv1gqvh"
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"text": [
"Scams are low key crimes overall even though they make up a large income base when put together. Although scamming someone for 200$ may be a high crime in one or two states it’s not worth the Feds’ time to track down some guy in the middle east or India making 2$ a day to call you on a spoofed number and act like tech support to steal 50$ from you. In many of these instances it’s better to track the guys paying the scammers, find out what heinous things they’re up to, get them for that, and then the scam groups die out. Until the next one comes up."
],
"score": [
3
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"text_urls": [
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[
"url"
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[
"url"
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|
haavh0
|
Can Wifi work under water ?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Water molecules is a dipole meaning that one end is positively charged while the other is negatively charged. This is similar to magnets but with electrical fields instead of magnetic fields. When you send a radio signal through water the electrical and magnetic field that the signal creates will rotate these water molecules as they try to align with the fields. This creates its own radio signal but with the exact opposite polarity. Thereby it cancels out your signal very quickly and just heats up the water. This is exactly how microwave ovens works, they even use the exact same frequency as your wifi router. So no, wifi will not work through water.",
"No, not for very far. The whole beauty of wifi is that it's very low power so you don't need transmitter licenses. Low power radio and water don't go together.",
"Radio waves don't get through water very well. Communicating with something under water usually requires a lot of power and very low-frequency radio. If both things are under water, sound works very well."
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3
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[
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|
habdi3
|
How does the needle of a record player ‘read’ the music on a vinyl?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"It vibrates. The needle is held at the base, while the tip is allowed to ride in the groove of the record. That groove causes the needle to vibrate (up and down, not side to side), and that vibration is picked up by whatever amplification method is used by that particular record player. In mechanical players, that amplifier was a big horn that acoustically amplified the sounds, while today the stylus (what we call a needle) is held by a cartridge that either has a piezoelectric element or actually has a small coil and magnet setup to turn the vibrations into electrical energy, which can then be amplified.",
"In a mono record, the easy kind, the groove wiggles from side to side. If it wiggles at 400Hz, the record player makes a 400Hz tone. The \"needle\" is free in it's mount to wiggle from side to side and each wiggle is turned into an electrical wave.",
"Shahking of the needle- > shaking of the membrane of the speaker- > shaking of membrane in your ear- > brain reads those shakes as sounds. & #x200B; Sound is wave. Vibrating of the air hit membrane in your ear and brain interprets this vibration as sound. Speaker is just big membrane that vibrate, to make sound waves, that your ear can translate to sounds, and needle just shake in groove to vibrate."
],
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29,
3,
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|
[
"url"
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[
"url"
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|
hacehi
|
whats the difference between a subnet and a VLAN?
|
I understand that both are used to separate networks into parts, but what makes them not redundant? why would one be used over another?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv20am4",
"fv215cz"
],
"text": [
"You typically use them together, but you don't have to. A subnet is a Sub Network that is part of a larger network. They are mostly used with IP networks, most notably IPv4. For example, you have a company that has 2 offices with about 100 or so people each. They are connected to each other over a VPN or WAN link. So you set up one office using the IP space 192.168.0.x and the other 192.168.1.x. Both of those are subnets. Then you set up routers so that the traffic can get from one to another. VLAN is a function of a network switch. Lets say you have a 24 port switch, and you have a need for 1/2 of it to be for one thing completely isolated from the other 1/2. You can set up 1/2 the ports for VLAN 1 and the other half for VLAN 2 and unless there is a router that spans the two port the two will never talk. Its essentially a way to take physical switches and divide them into multiple virtual switches (very simplified). A VLAN can also span switches if needed. If you have two VLANs like I show above, you will probably have two different IP subnets also. Though, that isn't a requirement. If the two VLANs are completely isolated from each other, you could use the same exact IP subnet on both and it won't cause any problems because the traffic will never see each other.",
"This will answer your question - URL_0 Basically, they can do the same thing (isolate a group of devices) but at different layers (data link vs network) and by different methods."
],
"score": [
7,
3
],
"text_urls": [
[],
[
"https://www.cbtnuggets.com/blog/cbt-nuggets/subnet-vs-vlan-whats-the-difference"
]
]
}
|
[
"url"
] |
[
"url"
] |
had1d1
|
Why are phone dial pads 1-9 left to right top to bottom but keyboard number pads are 1-9 left to right bottom to top?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv22866",
"fv2cs24",
"fv22q29"
],
"text": [
"Here are some theories collected by [Keyboard Trivia]( URL_0 ). The summary of facts: Touch-tone key pad was designed to mimic the rotary dial with the \"1\" on top and the 7-8-9 on the bottom, and AT & T conducted user testing to confirm that this configuration helped eliminate dialing errors. By the time when the touch-tone telephone was being designed in the late 1950s, the calculator and adding-machine designers had already established a layout that had 7, 8 and 9 across the top row. Back then, the industry-standard typical calculator had nine columns of numbers, with 10 numbers in a column, the lowest digits at the bottom, starting with 0 and moving up to 9, and was basically a mechanical adding machine that closely resembled a cash register. It is common practice today to use the telephone-keypad layout when designing new products that utilize a keypad, such as Automated Teller Machines. When Bell Labs began exploring keypad layouts in the late 1950s they contacted all of the leading calculator manufacturers to find out why they had chosen to put low numbers at the bottom and high numbers at the top rather than the other way around. The answer, apparently, was a big shrug. It turns out that decision was largely arbitrary: no one had done any research about which layout was most convenient for users. Still, when it came time to place a numeric keypad on a computer keyboard, the calculator model with 7-8-9 at the top prevailed. There's also a theory that phone engineers wanted to slow down people who were fast at entering numerical data, which would jam lines and produce dialing errors, so they reversed the layout. However, records of AT & T Labs' research clearly invalidate it.",
"My Japanese bank uses a touch screen for transactions and that includes the number pad layout. For security reasons, the number pad layout (for PIN entry) has the order of the numbers changed each time the ATM is used. EDIT: Added \"for PIN entry\"",
"The keypad on a keyboard is referred to as a 10-key and it's layout is similar to the calculators that were popular for accountants to make the switch over to computers easier. The layout compatibility wasn't needed for phones when the switchover to DTMF (Dual Tone Multi Frequency) as the speed of quickly dialing numbers actually interfered with the system that \"listened\" to the numbers you were dialing. At the time. That limitation no longer exists. DTMF dialing replaced the pulse dialing created by the rotary mechanism in old rotary dial phones. Each row and each column has their own tone, so when you press 1, the tone for the top row and the tone for the left column are played at the same time, the phone system \"hears\" these two tones together to know you pressed 1"
],
"score": [
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"http://web.archive.org/web/20180102203929/http://www.vcalc.net/Keyboard.htm"
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[],
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]
}
|
[
"url"
] |
[
"url"
] |
|
hadqtl
|
Why does a google search only take 0.000005 seconds while searching for a file by name on your computer take minutes and sometimes it never completes?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv289lm",
"fv26r4m",
"fv270hf"
],
"text": [
"Let's say you've got a big text book for a class. I ask you to find every instance of the word \"since\" in the book. You're going to have to go through the book page by page, and look at every word. But what if I gave you a different book that has a really, really detailed index in the back. You could just turn to the back of the book, find the word \"since\" in the index, and tell me all the places in the book where the word \"since\" appears. The search on your hard drive is like the first search. The Google search is like the second search. Basically, Google has already gone through all that info, and they've made an index for themselves, so when you search for \"cute cats\", Google goes to their index, finds \"cute\" and \"cats\" and gives you the answer.",
"Your hard drive is not as well indexed as the Internet because Google spent a lot of time and money indexing the Internet.",
"The google search process is being completed by a very fast, expensive computer network owned by Google while your search is being done by a consumer CPU. There’s simply more computing power in the google search."
],
"score": [
10,
5,
3
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[
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[
"url"
] |
|
hae89n
|
Why are printers so unreliable. How come we can make cheap computers, and smartphones that work without a hitch - but every printer is seemingly riddled with issues and a nightmare to use.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv2hmcf",
"fv2ahor",
"fv2aj8d",
"fv2n3ui",
"fv2e4f2",
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"text": [
"more moving parts. more variables. The ink is exposed to air so is constantly drying out. It needs to be precision but is made from stamped steel and injection molded plastics. It's hard to get paper to reliably move. why is printer software and firmware a fucking nightmare dumpsterfire? I dont know. Makes no fucking sense to me how a 50 year old printer company can make a wireless printer thats impossible to connect to wirelessly. Why the drivers dont work. They must turn misery into ink or something.",
"No incentive not to make a trashfire product since everybody does that in the market, basically. No enforced standardization means every company just does their own thing and the end result is an unmaintainable, incompatible mess. These companies sell ink, the printers are an afterthought.",
"inkjet printers are a racket. They are cheaply made and money is made on people buying ink which is more expensive than a fine wine per oz. Ink will dry up in the tubing or in the print head and cause all sorts of issues. People with any semblance of intelligence will buy a color laser printer which uses toner. It’s a higher up front cost but far more reliable and cheaper to use long term. Brother makes excellent laser printers.",
"We can make flawless printers, and they are used daily. Issue is, they are huge, professional units that are designed to shell out thousands and thousands of pages every day. The consumables are not an issue with them, partially because they are economic, and partially because cost of consumables is counted in price. Oh, did I mention they cost a lot. They cost a lot. Home printers ? Home printers are very, very cheap. You can get a very capable printer for pretty little cash. The thing is, printer companies aren't looking to make a profit on printers themselves, they are making money on replacement cartridges. Filling the cartridge with ink/toner is quite cheap and easy to do, but they sell cartridge unit as a whole. Those units cost quite a bit, and they really can't print all that much - not because they can't fit enough ink, but because you'll need to change it more often if it's smaller. People figured it out, and started refilling cartridges themselves, which is what printing companies do as well with recycled cartridges, so they started putting chips on them that count pages, and once a certaim number is done, even if you refilled it, it locks it out as an \"empty\" cartridge. So, the answer is, selling consumables for printers is far more lucrative than selling printers themselves. Money. That's why you're stuck with shit printers.",
"Printers are full of moving parts that have to work seamlessly or you will just get a mess. Also people don't want to pay real money for a printer that works well. If you buy a printer for like 300 bucks it will just work. I mean if you buy a phone for the same price as a cheap printer it will work like trash too.",
"A lot of it has to do with the medium itself. Paper comes in all shapes, sizes, and coatings, and tends to cling to itself and leave dust everywhere. The ink is messy and tends to dry out. And you have to somehow move this paper around quickly, apply ink to it in a precise way, and spit it out in a nice pile foot someone to pick up. That's a hard job for anyone to do, including humans. Printers get the job done by having a lot of moving parts that sense various things or perform one of thousands of critical functions, large or small. If even a single part fails the entire operation is put at risk. Now, these problems aren't insurmountable, and you could increase reliability of a printer, but it's going to come at a cost. The cost needs to be balanced against the marketability of your project and the risk management practices of your customer. In some areas, there is a low tolerance for failure on similarly complex tasks (think aerospace, for example), because a factory might be shut down or someone could die, or whatever. But with a printer the worst thing that happens is Jerry complains loudly about not being able to print off his stupid clipart PowerPoint presentation to give to Melissa in accounting. Someone eventually calls up their service rep and someone is out to fix the damn thing in a day or so. Businesses, therefore, are willing to accept a higher risk of failure for a significantly lower cost because the consequences of failure are relatively minor.",
"I am part owner of a commercial print facility. Large scale commercial digital printing devices are crazy reliable. I have a color medium duty Canon color laser digital “press” and it easily goes 500,000 large (12x18) sheets between maintenance. Like everything in life, you get what you pay for. Printers have a lot of moving parts and to keep them working well over many cycles requires replacing consumables.",
"I used to sell, service, and support wide format digital printers. They’re basically like your basic office inkjet blown up to 10 feet wide. The moving parts thing is an understatement. The technology and engineering behind printheads is mind blowing when you understand what has to happen. The problem is that HP and other manufacturers purchase printheads they don’t generally make their own. Imagine you’re driving a hover car and you have 4 paintball guns filled with a different color in each one. You have to paint a picture on the road perfectly. The paintball gun is loaded with various size paintballs and you have to instantly pick the correct size. The car is moving forward and back at about 80 mph. You also have to shoot each paintball ahead of you and it has to land in the correct spot while also mixing with the correct colors mid air.",
"It has a lot to do with moving parts. Computers don't have them, apart from the odd hinge or two. Printers have moving parts.",
"Cheap computers and smartphones dont have moving parts that are critical to their operation. ( fans dont count)",
"Very few mechanics in a Smart Phone, a little more in cheap computers. Printers are mechanical. Lots of moveable parts. Some metal, some plastic some rubber. Plenty of wear and tear. One motor not responding at the correct speed and you get a jam. Different grades of paper react differently sometimes tearing and leaving debris that builds up and causes other problems.",
"engineered to fail at the cheapest build cost. they make their money off of ink. you may as well be offered a free printer with each ink cartridge.",
"Consumer printers are often sold under cost (to gouge you on ink), so I'd assume everything (including the software) is designed as cheaply as possible. That said: a) get a laser printer, not an inkjet. Doesn't dry up, much better print quality for black & white, not even that expensive, and usually much less driver fuckery b) get the enterprise drivers if there are any. They're usually well hidden because they try to force-feed you the crapware, but if you find them, you can get a 3 MB driver package for a printer where the default install is 300 MB of pure garbage. If you're on a serious budget, don't mind turning it off when not in use (it'll burn through electricity like crazy otherwise), and have enough space, try to pick up a used but working business-grade laser.",
"Smartphones have no moving parts. Fundamentally there's not a lot that can wrong with them save physical damage or manufacturing defects. Inkjet printers have all sorts of moving parts and have to dispense incredibly precise amounts of ink at just the right spot on a piece of paper moving very quickly. There is a lot that can go wrong with something like that. The heads where the ink comes out can become clogged, the tracks can get bent, motors can wear out, all sorts of things. You can buy reliable printers though. I have a couple Brother laser printers I use for work and one has been going for 5 years now without a hitch. But it cost over $500. Worth it for me as the savings per print more than pay for it, but probably a bit much for an average user."
],
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|
[
"url"
] |
[
"url"
] |
|
haf1me
|
What are “32-bit games” and why the heck can’t my Mac run them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv2fqi7",
"fv2f6bx"
],
"text": [
"Some Number-bit in computing refers to how many bits of data (a 0 or a 1) can be transmitted/computed together. Computers started as 8-bit, then 16-bit, then 32-bit, and now 64-bit. 64-bit computing has been the standard for about 10 years now. Backwards compatibility for 32-bit software when the computer is running in 64-bit mode requires an abstraction layer to help a computer expecting data in 64-bit chunks process data coming in 32-bit chunks. In MacOS Catalina, Apple made the decision to remove that abstraction layer. You can still play 32-bit games but you will need to emulate a 32-bit operating system.",
"32-bit stuff are programs compiled to an older version of the machine language computers recognize as things they can run. Modern 64-bit CPUs can run them fine, but the operating system also has to support these programs. 32-bit programs are (nominally) no longer being created and are considered deprecated. Windows still supports it, Linux can optionally set itself up to support it, but Apple chose to just make a hard break and requires all the old stuff to be ported to the new system or get bent."
],
"score": [
10,
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hal9lo
|
how do they know how much happens in 24 FPS?
|
Standard frame rate for stop motion is 24 frames per second. But how do they figure out how much and the pacing of movement in that one second? I know how many strides I can take in a second but breaking that down to 24 bits... I can't figure out. So how do they do it? Just practice? Or do they do the motions and then speed it up /slow it down to 24 FPS?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv3huul",
"fv3kdmp"
],
"text": [
"I used to do very amateur flash animation, which is similar in a way that flash animation is basically just a really fast slide show, although usually, it was close to 12 fps. One trick that was used is that you have an initial frame, and you have an ending frame. So let's say you want your character to raise its hand from its waist to above its head. You have an idea of how long you would like that to take, say 1 or 2 seconds. so you have 2 frames, and you add a third frame in between which represents the midpoint between the beginning and end. Then you add another frame in between the first frame and the midpoint, and a 5th frame in between the last frame and the midpoint. You just keep adding these middle frames over and over again until you have between 12 and 24 frames. I would imagine there is something similar in stop motion but a little different given the medium. Remember that you can theoretically take as many pictures as you want, let's say 100 for some movement that you want to take 1 second. Then in the actual processing of the animation, you only keep every fourth frame. So instead of the 100 pictures you took, you only end up using 25. I would imagine that as you do more and more animation, you get better at intuitively understanding how much movement should be in 1 frame.",
"Well, you can start by watching reference material frame by frame. For example, if you're trying to animate a squirrel, you might start by watching some film or video of a squirrel frame by frame. Though after thousands of hours of the work, I expect you'd get better at it."
],
"score": [
4,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
halqx5
|
How do prosthetic limbs work? How does the person control them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv3kkvq"
],
"text": [
"So not all prosthetics are \"smart\" Some are just static. Some have some springiness to them to make walking feel more natural. Some are smart. They can attach sensors to muscles so that when you flex, it actuates a joint. Some newer tech uses other nerve endings, brainwave sensors."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
haobcr
|
Why do storage devices not have the same amount of storage as advertised?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv3x3xr"
],
"text": [
"Space is needed for filesystem overhead. Extremely simplified, that missing space is used for a table of contents. When you ask for a specific file, it looks in the table for the correct \"page\" instead of scanning the whole drive."
],
"score": [
8
],
"text_urls": [
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]
}
|
[
"url"
] |
[
"url"
] |
|
haozlp
|
What are the two small glass pieces next to US presidents while giving speeches supposed to do? Are they some sort of protection? how does such a tiny piece of glass protect a person?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv40sok",
"fv411e3",
"fv415it",
"fv40pid"
],
"text": [
"Those are teleprompters. They display the speech they are reading, so they can look up and in different directions instead of down at a piece of paper.",
"They are teleprompter. There's a projector underneath which reflects off the piece of glass, so the speaker can read from them. They allow them to read off a script while looking at a crowd. [here]( URL_0 ) is a video about how they work. It's pretty neat!",
"It is called a teleprompter. It allows the speaker to read his prepared speach while simultaniously looking at the audience. What you see is actually just a simple pane of glass. But it is mounted at a 45 degree angle. This means that when viewed from the podium you will see the reflection from the ground under the glass. By placing a monitor on the ground which shows the prepared speach it is possible to read the speach by looking at this piece of glass. This means that the speaker does not have to memorize his speach or look down at his papers all the time. The same technology is also used by television presenters. However they mount the teleprompters to the front of the camera so that they can read their script while looking directly into the camera. This is how news anchors are able to give so long and accurate descriptions of events which just happened a few minutes before. They are in fact reading their script for the first time and are just good at reciting.",
"Like this: I chose the last 3 presidents of the usa as this should not end in a discussion about politics, so just click on a random image or your favourite :D [ URL_0 ]( URL_0 ) trump [ URL_3 ]( URL_3 ) obama [ URL_2 ]( URL_1 ) bush"
],
"score": [
10,
7,
5,
3
],
"text_urls": [
[],
[
"https://www.youtube.com/watch?v=YeRu4xYH_W0"
],
[],
[
"https://s2.reutersmedia.net/resources/r/?m=02&d=20200224&t=2&i=1494574275&r=LYNXNPEG1N19B",
"https://georgewbush-whitehouse.archives.gov/news/releases/2004/01/images/20040120-4_a5bu6806-515h.jpg",
"https://georgewbush-whitehouse.archives.gov/news/releases/2004/01/images/20040120-4\\_a5bu6806-515h.jpg",
"https://cms.qz.com/wp-content/uploads/2018/09/obama-2.jpg?quality=75&strip=all&w=1900&h=1068"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hapfn5
|
How can search engines like google return billions of search results in fractions of a second?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv43tii",
"fv44k6q",
"fv47r79"
],
"text": [
"I will use book terms. When search engines find a new page, they create an index for that page. It then adds that index into “meta-index” so to speak. When you type something in, it calls on the meta-index and spits out all of the indexed links for the word, words, or phrase you are trying to search. It is like the index in an encyclopedia. It tells you what page the word you are looking for is on. It is then up to you to sort through the entries to find the information you need. It’s just showing you the results of work it already did.",
"There are dozens of reasons how Google or other major search engines can achieve this. To start, Google uses scraping bots to search the public web. When I mean public, it's typically anything not locked behind an authentication (like wikipedia). They use incredibly massive computers that run 24/7 to do this. Next, they process all this data and index it in an order that can be searched. Lastly, they use machine learning and other incredibly fast algorithms to use what you ( and millions of others) search and find the best results that were indexed. This all happens auto-magically as it's rare a human intervenes unless something critical happens with their algorithms that needs addressing. Another note is how popular a \"search\" is, for instance when you type \"what color is...\" There is a drop down of suggestions that possibly hundreds of thousands of not millions of people have already searched for has been reprocessed through their algorithms. Keep in mind that google processes 20+ petabytes of data a day, if not more.",
"By \"billions of search results\" you mean \"the results of billions of people making several searches at any moment\" or \"a particular person's search results in billions of answers\"? The first one is easier to understand, you just need a lot of servers for people to connect to and a lot of redundancy in their internal structure, so there's always a free slot for someone to make a new search. The second one is a little more complicated. Most of the hard and complex computational work is done even before you search something. Search engines have two sides: one is the \"public\" one that we use to query a search that searches only in a relatively small database; the other, the \"background\" one, is a monstrous structure that is navigating and processing the entire surface web at all times updating the database. In the background, search engines have robots navigating through links and reading pages trying to make sense of them. This information is used to create relationships between a page and another page and, also, between pages and some search terms. The relationships are used to discover which pages are relevant to certain search terms and also to measure how important they are. The first Google algorithm, called [PageRank]( URL_0 ), used only links between pages with the search term in their contents, but things are much, much, more complex nowadays! New and more sophisticate ways of making sense of a page content and extracting relationships, such as [machine learning]( URL_2 ) and [natural language processing]( URL_1 ) methods, are heavily employed. All this heavy work is compiled in a very complex database that is queried when we request a search, this is why it seems fast. Also, today, even the queries to the database have a lot of computational work done beforehand using the methods I cited above to understand what you are looking for and to sort the results more likely for you to be interested."
],
"score": [
16,
8,
3
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"text_urls": [
[],
[],
[
"https://en.wikipedia.org/wiki/PageRank",
"https://en.wikipedia.org/wiki/Natural_language_processing",
"https://en.wikipedia.org/wiki/Machine_learning"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
haq2o5
|
Induction hot-plates. Or induction in general.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv46p41"
],
"text": [
"Electricity is created whenever a conductor and a magnetic field are moving relative to one another. The induction plate makes a magnetic field that \"pulses\"; it moves relative to the pot/pan (which must be a conductor; glass, for example, does not work). The electricity generated flows through the metal of the pot/pan. Whenever electricity flows through a conductor, unless it's a superconductor, heat gets made."
],
"score": [
3
],
"text_urls": [
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}
|
[
"url"
] |
[
"url"
] |
|
has8vz
|
Why are infantry still used in modern war despite drones and tanks?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv4jvo4",
"fv4k6zt",
"fv4lech",
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"text": [
"Infantry take up space. If you want to control an area, you can't just blow stuff up. That causes destruction, but when the vehicle goes away, the enemy just comes back. You have to attack, which is hard, and then hold the ground. This way the enemy has to attack your entrenched infantry, which is hard. This is how winning works.",
"The modern approach to warfare can be lumped under the general heading of \"combined arms.\" Loosely stated, you use a variety of different units with different strengths and weaknesses to achieve different goals. Infantry, Tanks, and Drones can each do things the other can't, so they are all used to perform those tasks.",
"Infantry can protect tanks while tanks provide back up for infantry , the units work better together as they have completely different functions",
"It's cheaper to train an infantryman than to build drones and tanks. Additionally, tanks can't go into buildings(without destroying the building anyway) so when your objective is to take over an area you need infantry to go through the buildings looking for opposition forces.",
"Even if you could destroy the enemy with only tanks and drones - and thats a big if, given the inherent limitations of these things - you probably actually want do something with the conquered territory/city in the end. So you need to enforce rules and laws there. And you cannot really enforce laws with nothing but bombs and tank shells."
],
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"url"
] |
|
hasngb
|
How come when you x2, x3 , and so on the speed of a video or audio, the voices get a higher pitch?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv4m9af"
],
"text": [
"The pitch of sound is a function of its wavelength (higher frequency = higher pitch = shorter wavelength). The more distance between two peaks, the lower the pitch. When you accelerate the video, you effectively shorten that distance by compressing the soudwave (if you put speed at x2, peaks will come and go twice as fast), hence the higher pitch."
],
"score": [
18
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hasti3
|
What is Client-side Storage?
|
My current Adblock wants permission for unlimited client-side storage but doesn't explain what that means.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv4n36c"
],
"text": [
"That's storage on your device. Your phone, your PC, etc. The thing you're using is a client and the cloud or remote device is a server."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hata87
|
Why is 4G so bad now?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv4qncu"
],
"text": [
"More people use mobile networks now. Because the Frequencies used are limited they get shared (TDM and FDM). Because more people use the same Frequencies they get a smaller portion each, making it slow."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hatd11
|
How does the screen rotation of a mobile phone or similar devices work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv4xeof"
],
"text": [
"Most modern phones have two sensors in them called an accelerometer and a gyroscope, the gyroscope is pretty good at detecting which way is up, but it can be helped by the accelerometer which measures speeding up and slowing down in certain directions, once the phone uses the gyro and accelerometer to determine which way is up, if your phone is sideways it knows and rotates the screen to match the real world"
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hav10g
|
How does Minecraft limit the amount of storage space it uses?
|
For a game virtually infinite worlds, and hundreds of types of blocks how does it save and then reload that data?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv50bu1"
],
"text": [
"Well the world is virtually infinite. but you never really uncover the infinity of it. The world itself is generated by a starting seed so everytime you uncover a new chunk, it just calculates it from the basic seed. the only thing that needs to be saved are the changes you made in it as a player."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
haydjq
|
Why do so many loading screens go to 90% really quick, then take just as long or longer to finish the last 90%?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv5nrza",
"fv5t3j5",
"fv5sujp",
"fv5yx74",
"fv6oz1q"
],
"text": [
"Here is one example: A progress bar shows the total progress of all tasks being done. Each individual task might be different and it may not be easy to determine how long it will take (some recursive functions). So instead of calculating the progress of each task, it will just move the progress bar forward each time one is completed. So say there are 10 tasks to do: Task 1 of 10 complete, move the bar to 10%. Task 2 of 10 complete, move the bar to 20%. Task 3 of 10 complete, move the bar to 30%. And so on. Each of those tasks can take longer than the other so the progress bar can appear to jump in some places and stop in others, instead of a smooth transition from 0% to 100%.",
"Sometimes progress bars are not showing an actual progress of a process. They just “programmed” to go 90% in some period of time. This period is not always the same. Sometimes progress bar moves faster or slower. When process ends, a progress bar just goes from 90% to 100%. This is a common thing in web sites, when you need to show user that something is happening, but you don’t want to use an endless spinning loader. Source: I’m a software engineer",
"Imagine garbage collectors driving round their set path. 90% of their work is grabbing all the trash and putting it in their truck. When they get back to the dump, they need to empty the truck into the trash pile. Now imagine that while they’re dumping the trash into the trash pile, but bunch of the trash in the truck is really sticky and won’t come out easily. Now the workers need to go and scrape off all the sticky stuff and put it in the pile, which makes that last 10% of work much longer than expected. This is very similar to when a program is finishing what it’s doing and therefore ‘dumping’ its saved data that it doesn’t need anymore. Hope I helped a bit...",
"I worked for a game company once that intentionally added some time to a loading screen to ensure there is enough time to read what is going on. No sense having loading screen tips that last half a second. This was for a console and this was the only place in the game that conveying these small bits of information would fit. This was also a very light game so while it is one explanation, it is definitely not the most common.",
"Here's one of the simple reason other comments have missed out. They lie. There is no reason to trust the progress bar as accurate description of what's happening in the system. In an ideal progress bar, 0 to 10% should take same time as 90% to 100% by any reasonable definition of progress. Software companies lie about progress of completion to give us an illusion of completion. This happens all the time."
],
"score": [
139,
30,
11,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
haz2uf
|
Why do some processes not shut down even after pressing the X multiple times?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv5r2as"
],
"text": [
"The X sends a request to the program to run its own close code. It can be a fairly complex process, freeing memory, collecting garbage , autosaving etc. If the program was already \"Not Responding\" then that request is behind whatever it was already stuck on. The reason why ctrl-alt-delete and \"End Process/Task\" gets around this is that it instructs the CPU to close the offending program. You can even sever the thread entirely from the Processes tab, which will always kill the program fast but may lead to corrupted data. TLDR:. The X buttons code is in a queue and the software is busy or even hung. (Software Engineer) Edit: the above assumes no multi-threading. Putting those window controls into their own thread is one of the first exercises in learning to multi-thread,and would allow that code to run immediately. I also assume Windows OS."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb0g3t
|
what the hell are cookies and why do websites want me to enable?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv653p3",
"fv604bs",
"fv64z04",
"fv6074m",
"fv64tpm"
],
"text": [
"Imagine a website is like a hotel. The hotel wants each returning guest to have their room personalized to their requests each time they visit. They have millions of guests so instead of keeping a list of what everyone likes in a huge book, they write the guests requests on their foreheads. That way, there is no confusion and there is no need to identify everyone in a huge database. When a guest returns, they instantly know what they want without even asking.",
"They’re saved bits of information that help your computer interact with a site without you needing to do it manually. For example if you log in, your login info is saved and now your computer can identify itself and keep you logged in using a saved piece of data (cookie), instead of you needing to put in your password every time you move around or reload the site. They want you to enable them because they want to collect more info about you. They don’t *necessarily* know who you are, but if they know that the same person is viewing x, y, and z items in the same browsing session, they could advertise to them more effectively or show them content that interests them. And sometimes they do know who you are if you log in or connect the site to a Facebook account, etc. This is part of how modern sites make money, in order to provide services for “free”, but make people are still uncomfortable with it and choose not to enable cookies.",
"The reason you are starting to see these cookie notifications (were before they just happened and didn't tell you about it) is that new laws were passed by the EU requiring \"informed consent\" for information collection. Similar laws have begun to be passed elsewhere so website with a single (international) front-end are putting them up to avoid fines. Some websites automatically geolocate you based on your IP so if the site has a US landing page and you are reaching out to them from the US you will not see the cookie notice.",
"\"Cookies\" are tiny files that stay in your computer that a website can access and read. So let's say I am looking for a local store from a chain of ice cream parlors, and choose which store is local to me. The website can place a \"cookie\" on my computer, a tiny file that says \"This person's local store is #37!\" and then the next time I go to that website, it will look for the cookie, read the information in the file and then take me directly to my local store's page rather than asking me to choose which one is local to me again. This can make the internet very more helpful, but many people are worried about websites using this to put files on your computer without your permission, or that other websites may have permission to read those cookies and get information about you that you didn't expect. So the European Union passed a law that says that any website that wants to be legally available in Europe has to ask permission before putting a cookie on your computer. Since Europe is very large and important, that meant that pretty much every website that uses cookies has switched to asking so that they don't get in legal trouble there.",
"Web Browsers use a technology called HTTP to communicate back and forth with the web servers (i.e. computers) that host websites. One limitation of HTTP is that, in itself, it doesn't know the details of what's being talked about via its delivery service. It doesn't seem like that big of a deal, right? It's kind of like... Why should you need to be on a first name basis with your mail carrier to get your mail delivered correctly? Well it turns out it's a tad more complicated than that. Imagine if every time you communicated with the web server over HTTP — and I mean every time, every time you go to a new page or even click around on one page — you had to first pass along your username and password again. Otherwise if you failed to provide your username and password, the web page couldn't feasibly be customized to your experience. That would be like if the postal service insisted that, for every letter of substance they deliver to or for you, you must first send a signed fresh letter of consent via their service to the other party you're communicating with. How absolutely nuts would that be? Cookies try to solve this problem. And I realize the metaphor breaks down a bit, but I hope you see where I'm going with this. They're just a little bit of data (most frequently an arbitrary/random string of nonsensically arranged characters) that your web browser stores on your computer on behalf of the web server. Your browser and the server basically have a gentleman's agreement with how they will handle that cookie: the web server at URL_0 sends it to your browser, the browser agrees to store it safely (at least until an expiration date/time provided by server), and importantly the browser agrees to send that file to the web server every single time the two communicate. On the web server's end, the cookie is associated with your account somehow usually so the web server can look up who is communicating with it every time it gets a request for a web page. Edit: I forgot to answer why they ask all the time now. Some people believe asking fulfills a law called GDPR in Europe. Whether it does or doesn't is the matter of some debate, but the basic principle is that users should have an active say before they are made to have their behavior on the web tracked. Because cookies aren't just used for \"authentication\" like I gave examples above. There are different types of cookies (e.g. evil cross site cookies) that are used to track people for advertisement purposes."
],
"score": [
120,
20,
9,
8,
3
],
"text_urls": [
[],
[],
[],
[],
[
"www.whatever.com"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb1he9
|
In movie scenes where they use gunfire, is it mostly CGI sounds and flashes? Or do they wear hearing protection?
|
I am watching some actions movies and as someone who owns a few guns, there's no way they're using blanks with no hearing protection (that I saw), so is it CGI?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv66set"
],
"text": [
"There are two kinds of guns that are used in movies: 1) Real guns that are firing a blank with very little gunpowder in it - usually just enough to cycle the action and eject the cartridge; and, 2) Fake guns that have a small firework in the front of the barrel that produces a lot of sparks and smoke when the gun is fired. Neither of these makes a loud or gun-like noise, so the gunshot noise is added in post production. The further back you go the more likely it is that everything except the sound is real. However, the trend is increasingly to use a CGI prop - usually an object shaped like the gun but colored CGI green to make it easy to overwrite with CGI. If they're using a CGI prop the actor is holding the prop and pretending to fire, but what you're actually seeing on screen is CGI. There isn't really a good way to tell the difference between a real fake gun and a CGI fake gun as both can be anywhere from quite fake looking to quite real looking, depending on how much money was spent on the special effects."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hb1uh0
|
How exactly do headphones and Bluetooth headphones work? Is the sound being projected through the cable? And if so, than how does it work for Bluetooth?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv68q23",
"fv68jv5"
],
"text": [
"Headphones are speakers. Speakers work by taking an *analog* electrical signal and using that to move the speaker in a specific way. The cable is carrying that signal to the speakers. Bluetooth headphones are wireless, the playback device sends a *digital* signal to the headphones which is then converted to analog and then brought to the speakers. The difference between analog and digital is that an analog signal is literally just a current that moves the speaker in a very specific way to reproduce sound, a digital signal is 1s and 0s but the speaker is a dumb thing and doesn’t speak that language, so a digital signal must be converted to analog so the speaker can use it.",
"So, you know how you can get sound out of your phone, even though it’s not plugged in with a cable? Digital radio waves. They carry whatever information they need to carry. Sound. Pictures. Whatever. Bluetooth is just the name given to low-power, localised digital transmission."
],
"score": [
10,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb22yv
|
Why do most websites have a pop up asking me to accept that they store my “cookies”?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv69nfx",
"fv69qav"
],
"text": [
"Its a requirement in the EU that sites obtain permission to store cookie and tell you what they'll be used for.",
"The EU recently (in the last few years I think) passed a law that, as I understand it, prohibits sites from automatically collecting cookies. They now need to get your permission to do so and since most sites don't want to be banned in the EU they add that popup to their page just in case they get people accessing that site in the EU."
],
"score": [
8,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb2fiv
|
We have VRR displays now. When will we see Variable FPS videos?
|
Movies that show action scenes smoother but then move back down to 24fps for drama. Video security systems changing to higher fps when motion is detected and back down to minimal when nothing so as to save space. Overall use of newer hardware capable of better performance to bring experiences not possible before.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv6xqcf"
],
"text": [
"Codecs like H264 and H265 already do something akin to variable refresh rate. If two successive frames have very little difference, the codec will only store one frame and display it twice. This allows the effective frame rate for the video to be lower than the quoted frame rate, and is one of the reasons why videos compressed using these codecs are so much smaller than for older video codecs."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hb3lw0
|
How do solar panels work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv6k3s1",
"fv6kf4o"
],
"text": [
"Photons from the sun knock loose electrons from the silicone in the panels, the electrons attempt to attach to the secondary element in the panels, but get bounced back. All of this subatomic movement creates current.",
"Solar panels are made up of photovoltaic cells, generally silicon. This basically means they 'mess' with the atomic structure of two types of silicon strips, they give one strip a negative charge and one a positive charge and put them rreeeaallllyyy close together. Then they create a matrix of a bunch of these and put all of that on top of a metal sheet. Now once the metal sheet heats, by the sun, up those strips they grow just a tiny bit and touch each other bouncing their electrons around, this creates a charge which is then transported through to the metal and onto the wires in the back. That's the basic idea."
],
"score": [
14,
10
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb4qlq
|
How do we keep making faster cables.
|
I know with cpus the main increase is due to smaller transistors. What technology enables cables such as USB and HDMI to get faster over time.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv6wcub",
"fv7a6d0",
"fv6s155",
"fv7e9j0"
],
"text": [
"Its not just the cables, its the CPUs in the gear that's pushing the data. The cables are upgraded with better electronics to be able to handle the extra speed and data.",
"There’s a relatively simple concept that determines the bandwidth of a cable: how much data can you send and have it still be usable at the other end. In other words, you can send data faster and faster, and at some point it’ll be so fast that either a) the receiving equipment can’t keep up or b) the receiver can’t tell the difference between a real signal and random interference. The longer the cable, the more interference it will collect, making it harder for the receiver to figure out what’s real and what isn’t. For shorter cables like USB and HDMI, they get faster because the sending and receiving equipment gets faster, so they can keep up with faster data streams. For something like HDMI, where the bandwidth requirement is much much higher, interference becomes a problem, so they put more shielding on the cable to reduce it, making the cable thicker. For longer cables like coaxial, interference is the main limiting factor. Extremely thick cables help block the interference. On the other hand, fiber optic cables have virtually no interference, making the sending and receiving equipment the limiting factors. As the chips get faster, they can handle higher speeds.",
"There's more technology than you'd think in cables. Like a typical cat 5 cable is just 4 twisted pairs of wires. But the trick is that the wires are twisted at different rates to avoid interference. Then they crimp the ends without unraveling too much, so the wires stay in spec.",
"Cable bandwidth is impacted by very subtle changes in construction geometry and materials Increased precision of manufacture and better capability to simulate signal transmission has allowed subtle modifications to existing cables to create new versions with an increased effective bandwidth when coupled with the appropriate driving circuitry. These changes can be very small things, like using a different twisting-rate in twisted pair. Using a small plastic spacer to separate pairs. Having the connector terminate to the cable in a different way; different braid patterns on shielding. Using a different coating(s) that have better conductivity at high frequency. Even just manufacturing precision matters. For example -- making sure the conductor is /exactly/ the same diameter along the entire length of the cable This is why there are so many versions of most types of data cable. Each one has a small modification that improves it."
],
"score": [
8,
7,
4,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hb69cj
|
why a picture from my front facing camera doesn't look as good as just looking at myself in the mirror.
|
I feel like I'm ten times more attractive in real life than I am in pictures and constantly prove it to myself by looking in the mirror and thinking I look good, only to take my phone out and the image of myself onscreen looks nowhere near as good. What gives?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv711k3",
"fv735zn"
],
"text": [
"1) Angle; if you’re not holding your phone at eye level (which almost no one ever does without consciously thinking about it) the lighting and angles all change how your face is shown. 2) unless you’re using an app like snapchat or instagram, the front camera doesn’t flip your image, meaning it doesn’t flip it so your left and right switch, as you would see in a mirror 3) lighting. If you’re looking in a bathroom mirror chances are you have a direct light source within a few feet that help a lot. Taking a selfie in your room, you lack that and deal with more shadows and dark areas.",
"There are lots of reasons why [selfies don't match up with what your eye sees]( URL_0 ). A big one is the lens - selfie cameras usually have a wide angle lens to get more of the scene, but the trade off is that it distorts things that are closer to the camera, which distorts certain facial features. You can mitigate that by holding the camera further away (one of the reasons why selfie sticks are popular) or at a higher angle, etc."
],
"score": [
8,
3
],
"text_urls": [
[],
[
"https://oohstloustudios.com/the-science-of-the-selfie-no-you-dont-really-look-like-that"
]
]
}
|
[
"url"
] |
[
"url"
] |
hb8c4u
|
When my phone or laptop is turned off, is it 100% off or is it always slightly on?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv7didc"
],
"text": [
"There’s always a cmos battery that is keeping a slight electric charge going to make sure your system clock stays on and running. (It’s the watch battery on your motherboard). Other than that if you turned the device off, it would be off."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hb8hp9
|
How do car clocks keep the same time when you turn your car on and off?
|
If the power goes out, my microwave and oven clock need to be reset. But when I turn my car off, the time is correct when it turns back on. How do car clocks keep the correct time while being turned off, but the microwave and oven and alarm clock need reset. Now that I think, stuff like the GameCube also do this. They keep a consistent time even while turned off.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv7ebvd",
"fv7erl4"
],
"text": [
"Batteries. Disconnect the car battery and you'll have to reset the clock. The car itself might be off, but the clock is taking just enough energy to keep working.",
"Inside the car is the \"brain\" (computer) when you turn the key off the key turns off the motor, lights, ECT but the brain has a special permission to stay on. The brain uses such little power the battery will normally last week's or months because that's how strong the battery is compared to the brain. Each time you start the car it recharges the bit of the battery that was used."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hb9isb
|
What is Internet Relay Chat (IRC)? How does it work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv7krme"
],
"text": [
"Essentially it is an older form of online chat that happened to stick around until today. There’s no particular technical difference from modern chat services, apart from being a really simple text-only service. Also noteworthy is that it’s not a product like Messenger or Instagram, but a standard, meaning there are lots of different clients (the program on your computer) to connect to the chat you’d want, and anyone can host their own IRC server, which contributed to its longevity (doesn’t depend on a company wanting to shut it down)."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbbsum
|
How do fire alarms know when there is a fire?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv7vlbm",
"fv7vrsh"
],
"text": [
"Ionization-type smoke alarms have a small amount of radioactive material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm.",
"There are two common types: One shines a light through the air, and when there are particles of smoke, they're detected by a light sensor. The second type uses a radioactive source to ionize the air, and measures how electrically conductive it is, the smoke changes this."
],
"score": [
11,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbf6yo
|
When chips and programs went from 32 bit to 64 bit it was a huge leap forward, what is holding us back from going to 128bit?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv8fvnu",
"fv8gv3b",
"fv8qv5i"
],
"text": [
"The big change from 32 bits to 64 bits was changing the width that the memory controller dealt with so instead of being limited to 4 GB of RAM we can now use 17 billion GB of RAM (16 Exabytes), there isn't much point going up to 128 bits for a longggg while. In the early console days 8 bit vs 16 bit vs 32 bit was about the size of the data that the processor could work with, but modern processors work with data much larger than the addresses they can talk to. AVX (advanced vector extensions) instruction set was added in 2011 that let CPUs work with 128 bit data chunks, AVX2 expanded it to 256 bits, and AVX-512 is used on some of the Intel server processors to let them perform operations on 512 bit long data chunks We're unlikely to move to more than 64 bit memory addresses (most processors only use 42 bits right now) so you will likely never see a \"128 bit\" processor despite your processor handling 128 bit chunks of data on a regular basis",
"To the best of my knowledge the main reason is necessity. A 32bit CPU could only address a total of 4GB of system memory as 2³² gives us 4,294,967,296 addresses. A 64bit CPU gives us 2⁶⁴ which is 18,446,744,073,709,551,616 values such would allow us to use about 16ExaBytes of system memory and we're nowhere near requiring it. Bear in mind that an Exabyte is 1024 Petabytes, a Petabyte is 1024 Terabytes and a terabyte is 1024 Gigabytes. We're a long way off. The main issue people seem to have is that we live in a decimal world where 64 is just 2 X 32. Computers (hardware) live in binary where each bit l or BInary digiT can be a 0 or 1. So 1 bit is 2 addresses (0 or 1) 2 bit is 4 addresses (00,01,10,11) 3 bits would be 8 addresses (000, 001, 010, 011,100,101,110,111) And so on.",
"Lets say you're a postal service that has an automatic mail sorter. You find that if you limit the number of characters and numbers on the address to be at most 32, the automated sorter takes 0.01 seconds to sort each piece of mail. You sell letters with 32 blanks on it so the automated sorter scans them easily. Even if the address doesn't use all 32 blanks, it still has to check each blank and so can't go faster than 0.01 seconds. Since you serve a community that doesn't have a need for more addresses than can be represented with 32 characters, this works quite well for you. Then your community grows. Now, 32 characters isn't enough to account for each unique address. You need to allow for more characters if you'll hope to serve all your new citizens. You decide to upgrade the limit of characters on a letter from 32 to 64. Now you can fit a much bigger address in the 64 blanks provided on your letter, but it takes the automated reader 0.02 seconds to read each letter since it has to check twice the number of blanks on the letter. This doubles the time it takes to sort each letter even if it's address is 32 or smaller. 32, 64, 128 bits in this instance refers to how your operating system references memory. A 32 bit system can reference 2^32, which is 4 gigabytes, a 64 bit system can reference 2^64, which is about 16 exabytes. Every single time you move memory around outside of the processor, you need to enter it's full address though, and having a bigger address means a bigger number to compute, which means a bigger overhead. It's a trade off we're not going to make until we need to."
],
"score": [
23,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbjg0p
|
Can someone plz explain internet ping?
|
I see this term used in video games when checking on the internet connection, but I dont understand completely. Can someone explain?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv9680p",
"fv96d1w"
],
"text": [
"It's pretty simple. You send a packet out to some destination, be it a router or a server. That server gets the packet and sends a reply. You know when you sent it and when you got the reply back, so now you know how long your packet takes to get there, get processed, and return. Packets are also numbered, so if you send out \"1,2,3,4,5,6,7,8,9,10\" and only get \"1,5,8,10\" back, you know packets are getting lost. Shows if there are any issues with speed or packet loss along the way.",
"Ping is how long it takes for a signal to go from your computer to a server and back to you. A higher ping means that it takes more time to send and receive data; at higher pings, you will most likely experience lag/latency since it takes longer for your information to travel to the server and back. This is SUPER critical in video games where real-time actions are needed, like shooters, RTS games, and MOBAs, since your data needs to get to the server, then be distributed to the other players (and vice versa). A player with lower ping can effectively react faster than a player with higher ping since the lower ping player sends their commands/inputs faster to the server AND receives updates about the current status of the game faster than a higher ping player."
],
"score": [
4,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hbke70
|
How do radio stations know how many people are tuning in? And can they tell if people switch stations when they run ads or play certain songs?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fv9hio7",
"fv9fbrj",
"fv9ki8n"
],
"text": [
"There is a ratings company that measures this. It used to be Arbitron, but now Nielsen, which is far more successful, has become the main ratings tracker. Both companies used to rate TV and radio, but Nielsen became more famous and popular and Arbitron became less so and so they focused on radio, which Nielsen didn't emphasize. In I think the 1990s, Arbitron stopped doing TV and left it to Nielsen, and just focused on radio. But now Arbitron was bought by Nielsen and it's all Nielsen, with this service called \"Nielsen Radio\". They have a machine that tracks what channels people are listening to on the radio, and then there are surveys they fill out.",
"They don't, as the communication is only one way, the listener has no response to the signal, (the same ass cell phone would), so they rely on statistics,data analysis, patterns and surveys to know an approximate number of listeners and peak times, though peak times are fairly standard, and have been for a long time.",
"There's no direct way to know who is tuned to what because the radios don't store or broadcast that information. Most of that information is gathered later through marketing and research. Sometimes when an ad plays, you'll hear \"Mention you heard this ad on WFUK when you place your order for 5% off\". If the company suddenly gets an upsurge in orders where the customer said they heard the ad on WFUK, that must mean their ad is working on WFUK (but maybe not on KZOMG radio). Or a company will run basically the same ad on a dozen different stations, but each one will have a slightly different number to call. The moment someone calls in to order a widget, the company that is running the ad knows where they heard the ad on. Research companies also conduct polls of \"When you're in your car and driving to work, what station do you listen to the most? If you change channels, why? A) too many ads B) The ads don't apply to me C) I'm an ADHD channel surfing spaz\"."
],
"score": [
13,
11,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hboja7
|
In older gaming consoles (NES etc.), what does the number of 'bits' actually mean / what difference does it make?
|
Here's what I know: - A 'bit' is a binary digit (0 or 1). An 8-bit value therefore ranges from [binary] 00000000 to 11111111, AKA [decimal] 0 to 255. 16-bit values range from 0 to 65535. (unsigned) - I know what a CPU is, kinda. I know what volatile memory (e.g. RAM) is. I know what a hard drive is. But really I'm more interested in coding software than I am in hardware. Sooo.... does the bit number refer to the CPU, then? What does that mean? How is that connected to the number of colours / resolution that can be displayed? What's all this I've heard about 'bank switching' in older cartridge games?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fva4bz9",
"fva4tr9",
"fva5u6p"
],
"text": [
"With a CPU, the number of bits usually refers to the maximum number bits the processor can deal with in one instruction. For example, an 8 bit CPU can only add two 8 bit numbers together. If it wants to add two 16 bit numbers, first it adds the lowest 8 bits together, keep track if it needs to carry the overflow, then adds the next 8 bits together + the carry flag. A 16 bit cpu doesn't need to worry about all of that. It can just add two 16 bit numbers together in one step, which is faster. Now in the old days, with 8 bit and 16 bit CPUs, if your memory addresses were only 8 or 16 bits, that meant you couldn't access very much memory. So they came up with all sorts of hacks to allow more memory access without dealing with bigger numbers. One common way in the 16 bit era (8 bit is before my time) was to have a segment and an offset which were both 16 bits. When you were accessing memory, the segment was added to the offset and this was the memory address you'd access. So most of the cpu could only deal with 16 bits at a time, but logic to fetch and set memory could deal with more. Then the marketing departments realized more bits was better. So they'd look for any one part of the system that could deal with 64 bits and call it a 64 bit system, even if most of the cpu was still 32 or 16 bit.",
"For the most part, it refers to the CPU. But the CPU is such a integral part of the whole system that it affects everything else. All a CPU does is read and execute step by step instructions. The bit number basically refers to how big that instruction can be. An 8 bit CPU can only read the instructions 8 bits at a time. All instructions are binary, where each number tells the CPU to do something different. For example, 00000000 could mean add and 00000001 could mean subtract. That means with an 8 bit CPU, you can have 256 unique instructions. (It's wayyyyy more complicated than that and real world numbers will be different, but that's the idea). That means everything else is also restricted to 8 bits. An 8 bit CPU can only display 256 different colors because it literally can't read a color that's more than 8 bits. A 16 bit CPU can read instructions that are 16 bits long. Because there are bits it can work with, instructions can be more complicated and more unique instructions can be added. So basically more bits means the CPU can do more complex tasks. It can also understand 16 bit colors now! It's still relevant today. We're still in the middle of the transition from 32 bit computers to 64 bit computers. That's why many programs will have a 32 bit version and a 64 bit version.",
"It's the size of the numbers that the CPU can handle. So an 8-bit CPU can handle numbers up to 255 in one operation (e.g. adding 136 and 78). If you want to do anything with larger numbers (e.g. adding 214 and 93), you'd have to break it down into multiple steps. For example: 1. Load 214 (or 11010110) into register A (a register is a place to store a number). 2. Load 93 (or 01011101) into register B. 3. Add register A and B together, storing the result in register A. This causes an \"overflow\" where register A wraps back around to 51 (or 00110011). It also sets a flag in the CPU to alert the program that an overflow occurred. 4. If an overflow occurred, store 1 (or 00000001, duh) in the first byte of your final storage location (perhaps memory or a file). Otherwise, store 0 in the first byte of your final storage location. 5. Store the contents of register A in the second byte of your final storage location. This means your final storage location looks like this: 00000001 00110011, or 307. The bit value also tends to affect the maximum values of various hardware constraints, like memory size and colors on the screen, because those are also numbers that the CPU has to work with. I don't know much about bank switching but it sounds like it's using a two-step process to allow more memory access, where the first step is to identify the \"bank\" of RAM being addressed, and the second step is to identify the specific piece of data it needs to access. This allows it to basically double its bit rating (e.g. from 8-bit memory addresses to 16-bit), at the cost of taking longer to switch between banks."
],
"score": [
10,
3,
3
],
"text_urls": [
[],
[],
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}
|
[
"url"
] |
[
"url"
] |
hbpbk8
|
If we can get detailed images of galaxies and nebulas thousands and thousands of light years away of us, why can't we get images of planets in our galaxy, and possibly habitable planets (I'm aware of time dilatation)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fva7hyd",
"fva7a69"
],
"text": [
"It is sort of like asking why if we can take photographs of mountains several miles away, photographing an insect even a mile away is generally impossible. These are things of vastly different scale. A planet may be only a couple thousand miles across while nebula are more like several billion miles across.",
"The stars are extremely bright objects against an extremely dark background so they show up very well planets are much smaller and darker objects and are close to an extremely bright object so they are very difficult to see. Finding planets partly relies upon the stars being slightly dimmer as the planet passes between its star and us. URL_0"
],
"score": [
10,
3
],
"text_urls": [
[],
[
"https://youtu.be/AnYye_c8rI4"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbpgcv
|
how were maps created in old times?
|
Nowadays we got satellites and technology and before that boats and ships , but I'm wondering in Greek times or before that, how did people reach the conclusion of how each land mass looked? Edit: thank you all so much for answering this! The carrying responses made me realize probably more than one technique was used!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fva89rx"
],
"text": [
"Imagine you want to draw the outline of a strangely shaped building. If you walk around the outside of the building looking at the angles and length of the walls you could probably draw a reasonably accurate depiction of what it would look like from above. That's how maps were drawn but from a boat."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hbr09z
|
How do astronauts on the ISS get their oxygen and not use it all up?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvaicqu",
"fvaj3us"
],
"text": [
"They get a lot of their oxygen from supply craft. Similar to how they get food, water, new crew members, tools, etc., the supply crafts will also bring them air. In addition to supplies, they can also make their own oxygen by using electrolysis. Water is made from oxygen and hydrogen, so they use electricity to split the atoms apart from the molecule, leaving them with separate parts of oxygen and hydrogen. The combine the hydrogen with the carbon dioxide they exhale to produce more water. All of their supplies are carefully monitored, and by calculating how much oxygen they need per day, they can figure out how many days of oxygen they have. I suspect that they keep a minimum reserve, and always acquire or make new oxygen before they reach their safety margin.",
"[oxygen generators make new oxygen using water]( URL_2 ) that's brought up to the ISS on resupply missions; the hydrogen is vented into space. Carbon dioxide is removed by a system called [CDRA]( URL_0 ). > CDRA is a regenerative system whose principal operation utilizes 4 beds. Each bed ORU contains a desiccant bed and a CO, sorbent be-ence desiccantladsorbent bed ORU. The system relies on one desiccant bed to condition the air prior to entry into the adsorbent bed. The adsorbent bed selectively removes the COP, and the air travels through the second desiccant adsorbent bed to replace the humidity. Air is passed through a dessicant material to remove any humidity then passed through a mineral called [zeolite]( URL_1 ) which absorbes CO2. Once it becomes saturated with CO2 it has to be regenerated by heating it up releasing the trapped CO2 then it's vented overboard."
],
"score": [
76,
15
],
"text_urls": [
[],
[
"https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050210002.pdf",
"https://en.wikipedia.org/wiki/Zeolite",
"https://en.wikipedia.org/wiki/ISS_ECLSS#Oxygen_generating_system"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbs6tf
|
How does Windows know what's a valid product key and what isn't?
|
The computer doesn't contact other machines or databases to tell if a product key is valid or not, so how does it verify the validity of the key offline?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvatkh2",
"fvas5wm",
"fvb13ya"
],
"text": [
"It uses a form of [checksum]( URL_0 ). First, it turns all the letters into numbers. Then, it splits those numbers into 2-3 groups and does math on all the numbers in each group (e.g. adding and multiplying them). Then, it checks if all those groups gave the same number. Microsoft obviously doesn't publish what the specific groups are or the math it does is, because then people could make up keys that work. The math is complicated and specific enough that it's very \\*very\\* unlikely that things add up right if you just generate a random string of letters and numbers. Then, once you're online it checks that no one else has used that specific key.",
"The answer is that the product key itself will tell Windows whether it is a valid key or not based off of simply failing a checksum, or one of a number of other security features built into the product key.",
"Build-in checksum? yes. Can u trick the system? yes Use same key multiple times? yes, if it is not subscription based (O365) Is that 'legal? Probably not... Use RWEverything to fetch product key from motherboard in Windows 10."
],
"score": [
69,
11,
6
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Checksum"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hbve97
|
How do cameras capture an image? I'm honestly having trouble wrapping my head around the fact that somehow we can trap light and then put that light onto a piece of paper/screen.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvbcdmf",
"fvbc6d6"
],
"text": [
"I'm going to cover digital cameras. Older cameras used chemical reactions which I know less about. Lets start with a light sensor or [photodetectors]( URL_0 ). The light sensor can tell you how bright or dim the light it reads is because the more photons shot at it's reader, the greater current it produces. This is how it converts information from physical light to digital information a computer can understand. But one photodetector just tells how bright a light shining on it is. It isn't able to form an image from that. What if we had a big block of say 1000 by 1000 of them? Then we can see the different amount of light each photodetector detects. But if they're all exposed together, they'll all pick up around the same amount of light. So lets cover them up but cut one [pin hole]( URL_2 ) in front of them. Now each photo receptor is only being exposed to one small section of the image, just the part it can see through the pinhole. So if we convert each different value of current returned by the photo detector to a different shade of grey, we'll get a black and white image. 1000 by 1000 pixels tall and wide. But what about color? For that, we add a color filter. A green color filter blocks all light but green light, a red color filter blocks all but red, a blue blocks all but blue. Since these 3 colors are the same colors our eyes receptors care about, it's what we use in cameras. So to make a 1000 by 1000 pixel color image, we'll need to triple the number of photodetectors, We pack them in groups of 3 right close to each other with color filters in front of each. Now every photodetector with a green filter in front of it tells us how much green light it sees through that spot of the pinhole. Every red tells us about red, etc. We use all 3 to tell what color each pixel is. Each cluster of 3 isn't in the exact same spot. The blue may be a little to the left and above the green, but they're so close together that we can put all 3 color values they read in 1 pixel and it won't distort the image by much. [The Engineer guy did a great video on this topic]( URL_1 )",
"The first cameras used light-sensitive films. These special films have the particular property of changing colour when exposed to the light and thats where the camera structure ia needed. Thanks to the lens system, the camera captures the light reflected from the objects and lead it to the film, which, illuminated in some places by the light, creates the black and white photo. Modern cameras kinda have the same mechanism, what changes is the conversion of the light: instead of the light-sensitive film, there is a digital converter, which examines the light thanks to a light sensor and transform it in digital data. Then everything gets transformed into the photo"
],
"score": [
39,
3
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Photodetector",
"https://www.youtube.com/watch?v=wsdmt0De8Hw",
"https://thumbor.forbes.com/thumbor/960x0/https%3A%2F%2Fblogs-images.forbes.com%2Fbriankoberlein%2Ffiles%2F2017%2F08%2Fpinholediagram-1200x819.jpg"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hbzeg2
|
How does cooling work?
|
I understand that we use the fact that all electricity passing by a wire causes heat to use heaters and such. But how can we simply plug something in the wall and cold comes out? How does this work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvbwbf4"
],
"text": [
"You see, heating is an easy matter, because normally it comes as a waste byproduct. Cars produce unwanted heat, computers produce unwanted heat, it's pretty easy to make something that deliberately produce heat. Cooling is different though. Most cooling devices depend on a key property of gases, defined by the [ideal gas law]( URL_0 ). **The most important bit there is that when a liquid evaporates, it will take energy from the surroundings. It works the other way around, which means if a gas undergoes condensation, it will give off heat**. All refrigeration units basically go like this: 1. When you put a gas under pressure, it heats up. 2. Because it heats up, it will release heat to its surroundings. We make sure it properly radiates all the extra heat using condensors. 3. When it's cool, it will condense (like how water vapour condense on your cold drink). 4. This liquid has the built up pressure that the compressor puts in, so an expansion valve (a bigger pipe, really) reduces the pressure, because more volume = lower pressure. 5. The low pressure liquid is piped through a hot place (a room, a fridge) and as a result evaporates into gas. This gas is piped back to the compressor."
],
"score": [
4
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Ideal_gas_law"
]
]
}
|
[
"url"
] |
[
"url"
] |
hc62z0
|
Why did TV stations show a test pattern after going off the air instead of shutting the transmitter off?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvd4hfy"
],
"text": [
"Broadcast towers used (and in many cases *still* use) great big vacuum tubes as their power amplifiers. These expensive tubes can wear out, with most of the wear occurring during the warm up and cool down phases, or go out of adjustment. If you keep the tube warm at all times sending a signal, it'll last longer and stay adjusted so you can just pick back up in the morning."
],
"score": [
22
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hc7uub
|
When you have VR goggle lenses that are only a few centimeters from each of your eyes, when do you stop seeing improvements in resolution quality? As in, could a person with good vision distinguish between 1080p, 4k, 8k, 16k... etc?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvdiew4"
],
"text": [
"I suppose it would depend on the FoV of the lense/screen and the FoV of the video. For example, a 4k 180° video is gonna look twice as good as a 4k 360° video. You also need to keep in mind that at any given moment, you would only be seeing a small portion of the video, kind of like sitting in front of the tv with your nose pressed against it. So you have to measure this in pixels-per-degree. The human eye can apparently distinguish up to roughly 60 pixels per degree. The DK1 has a 90° FoV with a 640x800 pixel display in each eye, or 1280x800 total. This gives us 7 pixels per degree. In order to hit that 60 p/d goal, you would need 5,400 pixels per eye, or 10,800 pixels total for a resolution of 10,800x10,800 or something equivalent. But that would just be for a static image. While the FoV is 90°, most vr videos are 180°. So for a 180° vr video, you would need a resolution of (180°x60x2)^2. This turns out to be 466,560,000 pixels. So a video resolution of 21,600x21,600 or it's equivalent would be necessary in order for a 180° video to be indistinguishable from real life. Disclaimer: I did this all on my phone so I may have made some math errors. Just correct me if that is the case. Edit: Fixed a math error."
],
"score": [
3
],
"text_urls": [
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]
}
|
[
"url"
] |
[
"url"
] |
|
hc8qwk
|
Why is SPACE rarely allowed in usernames, emails, and urls?
|
SPACE is a regular ascii character, so for the computer there shouldn't be a difference. Dashes and underscores are allowed, while spaces are not. I wonder why that is?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvdm11n",
"fvdyyto"
],
"text": [
"How do you tell what's part of the email address and what is not? Eg, if I say: Email me at Dale [email protected] for help If spaces can be included in email addresses and URLs, you couldn't tell where the email address starts or ends. In fact, you can see exactly what happens by how Reddit tries to automatically format that link.",
"Space has a special meaning because there's no way to tell the difference between a space in one name and a space between two different words. There are ways to fix this. In programming (and command line interfaces) when something has a space in it you use quote marks so the space is seen as a character. Because this is complicated it's easier to just not allow spaces in names."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hc9kbx
|
Why are LED lights so much brighter yet more energy efficient?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvdxfse",
"fvdv04r"
],
"text": [
"Incandescent light is electricity going through a solid causing lots of heat in the process thus loss of power. CFL/ Halogen lights is electricity through gas. Much easier to go through with higher voltage so less heat. LED is basically a mini lightning bolt with a mirror in the back. Very easy to jump through thus little power needed.",
"Lights turn electricity into light and heat. Incandescent bulbs turn a lot of the electricity into heat instead of light. LEDs turn almost all of it into light and produce almost no heat."
],
"score": [
26,
10
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hc9m4o
|
Why is the infantry still relevant in modern war despite having tanks, jet fighters and guided missiles?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvdqxof",
"fvdqz9l",
"fvdqqda",
"fvduecy"
],
"text": [
"Because they’re the only way to truly “capture” a place as opposed to “leveling” a place. Ground armored units could possibly do this a bit but they’re actually really vulnerable without infantry support. Also, once you capture that place you need people there to enforce the new rules and new law and order, and you can only do that with boots on the ground.",
"None of the modern technological advances offer anything in the way of keeping control of a piece of territory once it's conquered. They can certainly assist, but they cannot hold territory. That requires people on the ground (infantry). That is the primary job of infantry in modern warfare.",
"Because unlike all of the things named. They can’t get into places like a building without reducing it to rubble or blowing it up and having pieces everywhere. Those things mentioned can’t retrieve intel. Infantry is still useful when you need delicacy not that their use is always the case",
"Because tanks are super vulnerable with infantry support and it's getting worst as better portable anti-tank weapons are developped. Because Bomb and missile are not magic. Factories can continue working even after a bombing, they can repair it, they can go underground, have bunker, hide in forest, jungle, mountain. You need infantry to capture, hold, defend, secure, protect territory."
],
"score": [
5,
3,
3,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
hca23p
|
Why does copying an image online to the clipboard on your computer happen instantly but saving that same image take a length of time to download?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvdtc49"
],
"text": [
"You're copying an image that's already in video memory, which may or may not be the original resolution of the image. The image you save may be many times larger in file size, depending on the camera and resolution, whereas a copy of a picture in vram cache is going to be just that, a copy of an image thats already been rendered to fit a certain size in your browser."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcclka
|
Why isn't every video game character hitbox perfect?
|
(Ignoring, of course, the cases in which the hitbox is smaller/bigger on purpose) I'm mostly referring to competitive shooters and that kind of games, where people want pixel-perfect precision. I know that the model that we see and the zone of the hitbox itself are two very different things, but here's my main doubt: You must create a 3D model for the character's look: then why can't you just say to the computer "THIS is the hitbox, copy that" and problem resolved? You are literally converting what you see into what you can touch. I tried to be clear. Thanks in advance
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fveatfq",
"fveau4q",
"fvec5uj",
"fvemae5",
"fvfui7z"
],
"text": [
"Good looking models have lots of polygons. Lots of polygons means lots of math. Computers have limits, so we make a simpler model for the hitbox, and now we can do less math, and the game still works pretty well.",
"The character model is composed of many, many polygons whereas the boxes are much more simple shapes. Hitboxes work by making the processor do lots of math. It has to run the calculations comparing each part of the projectile's hitbox to each part of the character's hurtbox to see if they meet anywhere. The more polygons comprise the hurtbox, the greater the load on the processor. Using boxes with very complex shapes that perfectly match the character model would harm the game's performance by overworking the processor.",
"Detailed character = milions of polygons Simpler character hitbox = smoother Gameplay It kinda works that way too with animations",
"Better hitboxes mean doing more math More math means a slower game Computers, like people, can only handle doing so many math problems at once. Imagine for instance your arm. Look at the hairs on it. Now imagine the hairs represent the hitbox. Each hair represents one point (like the corners of a box) the hitbox uses to make the shape around your arm. To move that arm the computer also has to move each individual hair. To move each hair the computer has to first figure out where the hair is going. This requires things like how fast it moves, when does it stop, etc. Once it does this it has to apply these numbers to every single hair every time you move. On top of that the computer also has to keep track of the state of the hitbox while moving. So let's say that a ball makes contact with your arm when it moves. Now the computer has to remember what it is supposed to do when you are hit with the ball. And it has to keep calculating where each hair is and where it is going while doing this. This makes it so unbelievably convoluted that the computer needs more time to figure things out. This causes slowdown, because the computer hasn't finished crunching the numbers yet and is behind on the work. Kind of like having a really hard piece of math homework due the next day you get in late not because you didn't do it, but because it took so long to do.",
"First, what the model actually looks like is calculated by your graphics card, long after the scene information leaves the CPU. The game logic doesn't know what the final image is. Second, hitboxes are detecting collisions between the model and bullets. [This is very, very computationally intensive process]( URL_0 ) which is drastically affected by the number of objects involved. Thus, replacing thousands of visible polygons with a few invisible cubes makes the process much simpler, with only a minor decrease in reliability."
],
"score": [
55,
10,
5,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Collision_detection"
]
]
}
|
[
"url"
] |
[
"url"
] |
hcgcik
|
why do screens use red, green, and blue.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvexmsr"
],
"text": [
"Red, green, and blue *are* the primary colors. In your eye, you have sensors called cones which came in three varieties, detecting red, green, and blue light. If you expect the primary colors to be red, yellow, and blue, those colors were chosen for artistic reasons. When painting, you start with a white surface and by applying paint, you make that part of the canvas absorb light of a certain color, hence what you see is the light that wasn't absorbed. Screens work in the opposite way, starting with a black surface, coloring a pixel involves the screen throwing out more light, not selectively absorbing and reflecting light. The inverse of red, green, blue would be cyan, magenta, yellow, and you'll recognize this as the colors that a printer uses. So where does red, yellow, blue come from? Well, fundamentally, you have to start with CYM when painting, but red and blue are culturally very important color to humans, hence being able to produce bright, vibrant reds and blues is artistically desirable but is rather difficult if starting from CYM. Cyan and magenta on the other hand, not so much. Hence, cyan becomes blue and magenta becomes red."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcgtmn
|
How were records such as military or criminal records kept before the age of computers? Did the record only exist in one central place or were copies of it at every precint/base? How were they updated?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvf3zyd",
"fvf387o"
],
"text": [
"Centralized locations were used to store hard copy information. Pertinent information is then dispersed as needed by other means of communication. Information just moved a lot slower.",
"As far as military I would assume it was a central place and copies were made/sent when needed. Criminal records were likely state wise, or central too if you look outside the US. Having copies everywhere that needed to be updated when new information became available is a huge chore and likely a deciding factor between centralized and decentralized archives"
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hckn18
|
Agile vs. waterfall methodology?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvgwd2l",
"fvfkj5l"
],
"text": [
"Waterfall is pretty easy to understand. If you haven't implemented and tested everything for your product, you don't release it. This leads to a lot of time spent developing and testing upfront, and only *then* you get your users to use it. Agile is a set of guidelines that encourage releasing products that aren't perfect yet, but are usable, so that people can tell you how well you're doing, and what needs to be fixed before you're done. The biggest difference between the two is really about when you get feedback from the user.",
"Imagine you are in the process of creating a music player. You can * Finalize the full design and every possible feature. * Implement the full application * Fix every single bug and issues. * Ship the product. **(Or)** Break down the music player into small components: The settings menu, the player UI, the file chooser, etc. In each week you aim to finish implementing one of these components. Say this week you chose to finish player UI. So you * Design the player UI * Implement the player UI as per design * Fix bugs * Fix bugs in other components * Move to the next component. The first method is the Waterfall method and the second one is known as Agile method. As you can imagine it's impossible to design the full product and every single feature. Requirements change with time and there will be some change or other. More notably, the waterfall model expects you to not revisit a previous step. So while implementing the app if you notice some design fault, you are not allowed to fix it. Which is not very flexible. Whereas in Agile method, you have multiple cycles of software development (known as sprints) where you fully implement small components of the app. You are also flexible to re-design the app or fix bugs."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hclxbh
|
Why do black and white pictures that were take like 40-50 years ago look so clear(like an hd image)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvfqoun",
"fvfwpek",
"fvfsm7z",
"fvg05io",
"fvgahpj",
"fvgsua5",
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],
"text": [
"Because they were taken with a film camera, which captures an image using light and chemistry with no pixels or distortion. That’s the same reason old movies can be remastered into HD or 4k.",
"Agree with most comments, except would note film is not pure analog, rather it does have grain. Grain is based on the photochemistry of the molecules imbedded in the gel, or film. Highly sensitive color film has larger grain (fewer “pixels”) than lower ISO film. Black and white film has the least grain, or smallest grains, most pixels. Sharpness of black and white film photos is governed more by camera shake, lack of focus, lense imperfections etc. My impression is a high quality 35mm color film photo, is similar to approximately a 20 MPix digital photo. Black and white perhaps 4x that in terms of grey scale, though obviously loses color dimension. Though these differences are indistinguishable online, large format prints, or extreme cropping, make them relevant. Small grain of B & W film, speaks to “colorized“ black and white photos as being very aesthetically pleasing...and historic...",
"Another reason is that some of those pics might have been taken by a medium format camera, where the negative is very large. Most handheld film cameras are/were 35mm sized negatives. Medium format is much larger and can be 'zoomed in' much more, giving a crisper photo when taken carefully. And if you own a medium format camera, you are more than likely to be taking your photos carefully. It's all very expensive at this point.",
"You ask about black and white pictures, but you don't mention color images from the period. I don't know if you are contrasting the black and white pictures from the color pictures of the time, since they are often faded. If so, the reason for the fading of color pictures is that the color is provided by special dyes or inks in the paper, which interact with the light. Dyes and inks are fairly complex chemicals and can break down over time when exposed to ultraviolet light (from the sun, for instance), causing them to fade. This is the same thing that can happen to fabrics or paints that are left in the sun for a long time. Black and white photography does not use dyes but instead uses silver. Black and white films and papers have a chemical compound of silver in them. When exposed to light, this compound would change so that, when it was developed, the compound would leave behind tiny grains of silver. Where it wasn't exposed to light, the compound would just wash away, taking the silver with it. The silver left behind looks black to us. Since it's just silver, it doesn't fade over time because there really isn't any way for it to break down.",
"The clarity of an image comes from the quantity of information it contains. Now, “information” is a fascinating and subtle topic, but for our purposes we can think of the amount of information in a photograph as the number of pixels—in a black and white photo this is especially simple, in that we can divide the picture up into a grid of black or white dots. Each dot is a pixel, and the total number of these dots is the resolution of the image, and resolution (or “definition”) is another term for the quantity of information. Higher resolution is more clear. HD is High Definition. If you’re thinking “Wait, old cameras has film, they don’t have pixels!” you’re right, but it turns out that light sensitive chemical photography does have “grain”, which is the smallest bit of information that the film can record, and for our purposes, we can basically treat electronic pixels and chemical grain as the same idea: a measure of information. So why do older photos seem to be more clear? They contain more information! The reason is that the chemical film could pack way more light sensitive grains into the same area than digital electronic sensors. As technology proceeds, the number of electronic pixels has increased. Only relatively recently has digital caught up. And even then, there is also the question of how big your _first_ image is. Every picture you see on a screen or printed out is a copy of that first one, and will never have more information than the first one, which was made from light striking a photosensitive area, whether electronic or chemical. So the size of that area, and the size of each pixel determines the quantity of information: small pixel, big area gives you the most information. Older pictures are often made with cameras that give the best of both worlds. They used chemical film (or plates) that both fit more pixels into an area, and were much larger than any commercially available electronic sensors. A professional sensor now might actually be 35mm, which was basically the smallest film size. I have several cameras which use 120mm, and one that makes a first image in 4x5in. That’s just so much more information! That’s not even the largest commonly used format in the history of photography. Film captures a lot of information for cheap, so old film photos are the original HD",
"40-50 years ago? that was like 1980... who was taking black and white photos in the 80s",
"Because they were taken with larger pieces of film with smaller grain than most photos taken today. The big film captures more definition",
"Film doesn't really have a resolution, so with good film you capture light as it is. Making it in our digital age as HD as possible !"
],
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394,
58,
14,
9,
9,
5,
5,
5
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcn28p
|
What does memory usage mean in a game and what causes high memory usage?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvfxwm4"
],
"text": [
"Memory (also known as \"RAM\" or Random Access Memory) is a space where a computer temporarily stores data that it needs to access quickly, whereas other storage (like a hard drive or disc) would be too slow to read from. Games use RAM to store assets (like models, textures, level layouts, sounds, etc.) so they can load them quicker, to be seamless to the end user without having a lot of load time. Some games use a lot of RAM, either because they have a lot of assets to load all the time, or because they are poorly coded and aren't using RAM efficiently."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcqnap
|
How's hacking really done? The movies make it seem so simple
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvgm3rb",
"fvgra15",
"fvgsn4g",
"fvgrg28"
],
"text": [
"Typically it's exploiting human error, like phishing links, where a fake email will get a user to type their information into a duplicate website. However, the more interesting way hacking is done is by exploiting holes in the software/hardware security. Like typing code into an input that is then ran by the system, which can then reveal private data or give insight into other kinds of attacks. Sometimes there is oversight in actual hardware, where private bits can be cached in accessible registers. It's very case by case how hacking is done, however, sometimes that case exists in a lot of machines or a single breach reveals a lot of information.",
"The most prominent would be Social Engineering, which boils down to basically tricking people into giving you their password, this can be as simple as asking them, or going to their facebook to find the name of their dog for the secret question. But this isn't really the type of hacking you are talking about. If you, as nefarious hacker would like access to a certain server, you would generally start up a program that tries to determine what kind of software is installed on the server, to see if the owner neglected to update any of it, and left software installed that have known exploits. Then after that, you use a program that tries several known exploits to obtain access to the system. At that point you are hopefully in. If this doesn't work... then instead of going on a long gruelling search to pinpoint the weakness in the system, the hacker just gives up and tries another target. Exploits generally involve you sending a weird/wrong request to a server. and the program on the server that handles that request doesn't handle it correctly, Like refusing it outright. Instead tries to comply, and does the wrong thing. Basically you are making that stupid \"Dumb-ass-says-what\" joke to the server, and it actually works if you do it in just the right way.",
"There is no straightforward way of hacking something. Hacking is done by exploiting vulnerabilities, which are created by people who write software. I think most answers you will get to this question will be quite vague, so I though I would give you some specific examples of instances where I, as a software developer, have to be careful when writing code. When a user authenticates, they will typically provide a username and a password. In order to perform the authentication the developer have to construct a database query that contains the information the user provided. If it's an SQL database, it might look something like this: SELECT \\* FROM USER WHERE ID = < username > Where username is the string of characters the user input in the username field. Here, the developer has to make sure that the content of < username > doesn't contain information that would be interpreted as an SQL command in and of itself. Managing to insert your own SQL commands in this way is called SQL injection, and could, depending on implementation, give you full access to read or even delete the entire database. Another example, not involving database access but rather the memory allocated for a program to run, is a buffer overflow attack. This is mostly associated with older languages such as C, where you explicitly allocate memory for holding data. Simply put, a buffer overflow happens when the length of the input from a user in not checked, and exceeds the expected length, allowing the user to write arbitrary information into a segment of the memory they were not supposed to have access to. This would in most cases simply result in the application breaking, but with very deep knowledge of the system and well crafted input, it could give the user access to unauthorized data. A third example is something I spotted very recently in a code review (basically a coder asking colleagues to read their code before they push it to the central code base). In this example a the code was asking the operating system to read the file /path/to/file/ < filename > , where /path/to/file was defined by the coder, and < filename > came from a web interface. Any information coming from a web interface should be considered insecure; a tech-savvy end user can always circumvent rules enforced by a web app since the web app is running locally on their machine and they have access to the source code. For example, if the user only can chose 5 different files from a drop-down list, one still have to make sure that one of these 5 was actually chosen by the user (at least if there exist some other value that might put your system at risk). Anyways, this specific implementation made the software vulnerable to a so called directory traversal attack. If they started their \"filename\" with \"../\" it would allow them to access the parent directory. With \"../../\", the parent of that directory, etc. This would allow them to read arbitrary files on the file system, assuming the application itself had access to them. My last example is an attempt to insert a backdoor in the Linux kernel, which is quite simply explained [here]( URL_0 ). Simply put, someone tried to sneak in a code change that at first glance might just look like an error check, but in actuality elevated the privileges of whoever executed that code to root. Getting a backdoor put into software used in so many places is obviously very valuable. On this point, it's also worth noting that when we develop anything on a larger scale, we will be using tools (libraries, frameworks and applications and operating systems), written by other developers. These will typically at some point contain known vulnerabilities that eventually get patches, but because it is quite common for organizations to lag behind on software updates, a hacker would just have to identify an outdated layer in a technology stack and exploit a well-known and well-documented vulnerability. Most software wouldn't be able to fulfill its purpose if we didn't allow its users to interact with it and modify it. At the same time we need to make sure that they can only do the things they're allowed to do. Software is written in a very abstract and generic way, and it's very hard to conceptualize all the ways in which the code can be executed. Writing secure code is therefore very tricky, with lots of pitfalls, that if overlooked can be exploited.",
"It's both simpler and more complicated than what movies show. Non-technical approaches often fall under Social Engineering: getting the victim to give you the desired information. A common and crude example is to call them pretending you're from tech support, and ask them for their password. In the past, this has been shockingly effective. Every major institution still has to virtually scream at you that their employees will never ever ask you for your password. Even more technical \"hacks\" often exploit that the weakest link in security is the user. Phishing is one of the more popular approaches. You've undoubtedly received emails that try to get you to click a link and/or enter your login information. If you click the link, it tries to install a virus. Purely technical approaches often revolve around \"vulnerabilities\" in the software running on the target computer. These can be very simple or extremely complicated, and can have all kinds of results. Some vulnerabilities can only slow or crash the target software. The most dangerous ones allow the attacker to run their own code on the target computer. This would be the only category worthy of the movie cliche \"I'm in!\". Just as with legal software, there are beginner and expert hackers. The experts may also create software attacking one or more vulnerabilities, and then sell it to beginners. Most of the malware out there attacks everything it sees using one specific technique. Often it fails, and sometimes it works. It's a fact of life for any server that it is constantly under attack by automatic scripts. Most of these attacks are like a burglar checking whether you left the door wide open. Some of them check whether you've left it unlocked."
],
"score": [
32,
9,
4,
3
],
"text_urls": [
[],
[],
[
"https://freedom-to-tinker.com/2013/10/09/the-linux-backdoor-attempt-of-2003/"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hctxw1
|
How is it with app updates? Do apps get progressively bigger with more of them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvh65vc"
],
"text": [
"Not necessarily. Updates can be things like \"replace this old code with this new code,\" or \"replace these old image files with some new ones.\" If the update is adding features, then yes, the app would get bigger, exactly how much bigger depends on the features."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcuebd
|
Why modern cellphones still struggles to run a emulation such as psp games even the game is old?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvhk5ew"
],
"text": [
"Because emulation is the process of pretending to be other hardware. That process takes it's own cpu cycles on top of actually running the software. A simple analogy would be like talking to someone else in a language they don't understand with a translator between you. Your conversation will be slower because the translator has to translate everything you each say to each other."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcuzia
|
Why are so many major store's websites absolute garbage?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvheab0"
],
"text": [
"All those other companies are solely web based. They have a vested interest in making their webpages provide perfect user experience. The stores you mentioned (except amazon) get most of their profit from physical store locations, so the webpages are a hot mess maintained by interns."
],
"score": [
22
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcwgi1
|
How does a game get easier or harder when you switch difficulties?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvhlmk0"
],
"text": [
"Most of the time it changes things like how much damage you do to enemies and how much they do to you, and how much health you/the enemies have and how fast (if ever) it regenerates"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hcxpbf
|
How hydrogen fuel cells work in vehicles vs ICE?
|
I never really understood much about the drivetrain or ICE and now the world seems to be moving towards lithium ion batteries in cars and hydrogen fuel cells. Can anyone explain the process by which fuel in converted into energy in a hydrogen car vs an ICE and what makes it so environmentally friendly? Thanks! :)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvhv1ot"
],
"text": [
"An ICE - Internal Combustion Engine - is the kind of engine everyone already has in their gasoline-powered cars. Mythbusters once showed that if you had a car with no gas and instead fed hydrogen (with normal air mixed in) into such an engine it can start and run. (Mind you their experiment was not very safe and the hydrogen blew outside the engine as well!). While engine redesigns would be recommended this could be a way to run a hydrogen car. A fuel cell is completely different. Instead it's like reverse electrolysis. Hydrogen from your fuel tank + Oxygen in the air produces water and you get electricity right out of the process. This then goes to an electric motor. So it's like a battery powered car but uses hydrogen for the storage rather than batteries. This is a more efficient use of hydrogen vs the ICE method, but such fuel cells are also expensive and have other issues. Last time I looked (which was a few years ago) you needed to use expensive metals and they have temperature tolerance issues which can make them a problem to use year `round. But in either case, the chemical process is Hydrogen + Oxygen = Water + Energy. No carbon dioxide is produced, making this a very environmentally friendly car. But like a battery electrical car what matters is how you get that energy. The best way to make hydrogen in huge quantities is breaking down fossil fuels which still makes carbon dioxide with your hydrogen. So yeah...."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hd073k
|
with slow internet, why do ads load without fail but content is stagnant?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvidwng",
"fviha0t",
"fvis3zb"
],
"text": [
"Ads are hosted on servers run by Google or the like, and so are very fast and reliable. Content is hosted by whoever owns the site and sometimes that hardware is a potato.",
"The ads and the content are in different places. Let's use Google ads on a personal blog for example. There are many Google servers, and the ads are already queued up for you, but you still need to connect to the website. Think of it like going into a restaurant. They'll have the menus ready for you right away, because they already know you want them. That's like the ads. But you still need to order, have the food made, and have it brought out to you. That's like the webpages loading. Now a popular restaurant may have lots of staff to handle everything quick as possible, while in a small restaurant, the kitchen may be tiny, and you'll have to wait for the previous orders to be completed before they make yours. That's like a popular website having multiple servers, or a personal blog having one server that's also taking care of other smaller websites. Faster website, and slower website. Of course there's more to it than that like your computer, your wifi connection, your internet connection, etc that effects how fast a website may load. But we won't get into that.",
"Browser's caches has great role in it. When an ad, usually an image, loads for the first time, the browser cache it and the ad served from the cache for subsequent requests."
],
"score": [
19,
8,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hd0l1o
|
how does wireless in cars work?
|
I am assuming it just uses data like your phone right? If so who is paying for that data? And if it’s the driver and owner then why not just use the data without the “WiFi”
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvigofc"
],
"text": [
"It's a subscription. For example, on GM vehicles you can subscribe to different levels of OnStar, some of which include the data. Of course there are promotions, like when you buy a new car the first month of data may be free. It's 3G, LTE, eventually 5G, just like your phone data. Why not just use your own data instead of connecting to the wifi? Well that would be great for your phone. But what about the kids phones that aren't subscribed to data. Or a tablet. Or a laptop."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hd1cuz
|
How does Whatsapp make money? They don't show ads. Messages are end to end encrypted, so they can't make use of user data. I tried to google it but could not find any answer that satisfied me.
|
Edit: Some of you have replied by saying that Whatsapp is not a money making business right now. But wouldn't they be losing millions of dollars due to cost of buying servers and maintaining them for the users? I can't understand why they are giving this kind of service for free.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvihfcg"
],
"text": [
"As of now, WhatsApp isn’t a profit-making business line for Facebook Inc alone by itself. In it’s initial days, WhatsApp used to charge $1 per user per year (after the first free year). That was eventually dropped down. As of now, Facebook is trying to monetise WhatsApp in two ways: 1. **WhatsApp Pay** is a digital payments service in-built within WhatsApp. This isn’t available in all markets and to all users. Digital payments has a huge potential by itself. 2. **WhatsApp for Business** is a conversational platform for businesses. Businesses can use these to keep users informed of their bookings and send confirmation messages instead of plain-old SMS; or to create conversational commerce provider. In India, JioMart was launched recently that allows user to make purchases from within WhatsApp. Pitch in the digital payments too, and this is a recipe for loads of money. A potential to be WeChat of the world. In conclusion, revenues from both digital payments and business messaging would be significant in future, and maybe are something meaningful even now."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hd8ile
|
Why is downloading so much faster than uploading?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvjlutq",
"fvjm9kn",
"fvjo7pt"
],
"text": [
"Because most people only ever use download and ISPs know that, so they focus the available bandwidth on downloading. There are not that many people who need to upload 50+GB, but downloading a game is pretty common",
"The practical reason it's that way is because while download speed is important to the end user, upload speed is not. Virtually all Internet traffic you engage in is asymmetrical. If you stream a movie, you need massive amounts of download bandwidth but you only need a tiny amount of upload bandwidth to send the initial \"stream me a movie\" command. For mobile devices in particular, there's also the consideration that the cell tower - attached to grid power - is significantly more powerful than your cell phone. Since transmitting generally costs more power than receiving, having a high download speed is a lot easier than a high upload speed because the amount of data you can send is related to the power you're willing to expend. In mathematical terms, imagine you're in a market where there are 5 lines that converge on a single checker. Each of those five lines is delayed by the fact that it has to wait for the other lines to process as well. On the other hand, if there's some item the checker wants returned to the shelves, they can simply pass that item down the one line closest to the appropriate shelf without delaying any of the others. The \"downstream\" bandwidth is effectively five times the \"upstream\" bandwidth because there are five parallel lines going downstream while there is a single chokepoint on upstream. When you're sitting at home on your residential Internet, you're one of many people whose traffic all converges on a single distribution node of the provider. That being said, institutional customers commonly purchase symmetric lines that have the same upload/download bandwidth because they have high upload demands. Indeed, it's likely that a company like Netflix is weighted the other way - they pay for enormous upload bandwidth, but not much in the way of download bandwidth.",
"Traditionally download was more useful, and more of the bandwidth were allocated to that. As technology improved and bandwidth increased, some companies stuck to that tradition even if they could provide symmetrical speeds. Most companies now offer symmetrical packages. Edit: If companies are offering slow upload speeds, contact your isp and complain or suggest they upgrade it. Even if it's their social media account."
],
"score": [
31,
7,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hd9pcw
|
Why do music and podcast apps give warnings about downloading something over data, but not when streaming something over data? Wouldn't they use the same amount?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvjuf4f"
],
"text": [
"Not necessarily. Streaming is only using data while you're actively listening. Let's say it's a 1 hour podcast and the file size is 100MB. You could download it which would definitely use the entire 100MB, or you might stream only part of it, get maybe halfway through, and you've only used 50MB in that case. ETA: Some apps use lower quality audio when streaming as well. Apple Music by default will give you a lower quality stream when on cellular. (You can switch this option in Settings.)"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdbyo9
|
Why does the shuffle function on all of my music libraries always seem to play a select few songs often and the rest of the songs are played sparingly?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvk7s8w",
"fvli9kx"
],
"text": [
"Some music players give priority to songs it deems \"favorites\", based on number of plays. Any song in your shuffle list that you've played more often is likely to get played more often, which in turn reinforces the apps idea that you want it played more often",
"In short, the problem is your brain, not the music player. This is an example of the [Clustering Illusion.]( URL_1 ) Humans are just really bad at determining whether an order is random. [Spotify has a great blog post]( URL_0 ) going into detail about their shuffle algorithm; when they initially launched, their shuffle was truly mathematically random. However, they got a lot of complaints from people who said it didn't *feel* random. So they now use an algorithm that is designed to make sure that songs from the same artist aren't too close to each other in the shuffle order. From a mathematical perspective it is less random, but users like it better."
],
"score": [
6,
3
],
"text_urls": [
[],
[
"https://engineering.atspotify.com/2014/02/28/how-to-shuffle-songs/",
"https://en.wikipedia.org/wiki/Clustering_illusion"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdc6o0
|
How does a garage door opener only open MY garage?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvk9d3x"
],
"text": [
"Garage door openers operate on different frequencies typically in the 300mhz range. So first of all your remote has to be a compatible frequency compared to your neighbors garage door openers. Then there's the code. Most garage door openers have a set of dip switches inside that act like a combination code. The code in the remote has to match the code programmed into the garage door opener. If you have 8 dip switches with 2 positions each that's 2^8 or 128 different combinations. If there's 12 then there's 2^12 or 1024 different possible combinations."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hde0x5
|
- How do smart scales tell you such detailed info such as water percentage, visceral fat and muscle mass just from standing on them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvkrmfg"
],
"text": [
"I work in a field where these Bioelectrical impedance analysis (BIA) Scales are used a lot so we'll start with the ELI5 and a bit longer explanation after that. ELI5 The BIA Scales are basically guessing almost every thing and they've gotten so good at guessing, that they can be considered a valid measurement method. It's like tasting a cup of hot chocolate and based on the taste, exactly figuring out the amount of cocoa-powder inside the cup. Yeah you can make a guess based on the size of the cup, how much milk is inside, the color and the sweetness, but it's still just a guess! After doing that ten thousand times you'd be quite accurate, but you could still be fooled by adding, for example, sweeteners. LONGER EXPLANATION The pads sent a slight jolt of electricity from one side to the other and measure how much electricity made it from one Pad to the other. As our muscle cells are filled with water, and fat cells have a lower water percentage, more electricity is lost if it has to travel through a lot of fat. Based on the electrical resistance or impedance of your body, everything else (Muscle mass, visceral fat, body fat) is calculated (or guessed) based on formulas. These formulas are based on hard scientific data taken from other methods of measurement, but the scale is basically guessing. You can try this yourself: Stand on your scale in the morning, and then again after you come home from work. You should have less fat in the evening! Because while lying at night, the water is distributed evenly throughout the body but when you are up and walking or sitting, more water is in your legs, lowering the resistance of your legs. Or for a faster effect measure yourself before and after taking a bath."
],
"score": [
13
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hde2h4
|
What is x86 chip architecture?
|
Ever since there have been rumours that Apple might switch to ARM processors everyone has been up in arms (if you pardon the pun) about x86? What exactly is this, is it intel specific or does AMD chips also use it?? Why is losing x86 a deal breaker for so many people?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvkox6s"
],
"text": [
"> What exactly is this x86 is a CPU instruction set. It's essentially a standard that describes the capabilities of a CPU. All x86 CPUs implement those capabilities in one way or another. Having a standard instruction set like that makes it much more easier to develop software and hardware that work with each other well. > is it intel specific or does AMD chips also use it x86 gets its name from Intel 8086, an 8-bit chip Intel released all the way back in 1978. They developed that chip's instruction set all the way up to 32-bit over the years. They licensed the chip's architecture out to other manufacturers, so they weren't the only company using it. In the early 2000s, AMD built a new 64-bit architecture built on x86, which is now called x86_64. Nowadays almost all desktop and laptop CPUs use the x86_64 instruction set. And x86_64 is what Apple will be ditching, if they ever go through with it. ARM is another architecture developed by ARM. It's a well established architecture, but it has different design goals than the x86_64. Although it is not as powerful as x86_64, it uses a lot less power, which is why it is so common in mobile devices. The iPhone has an ARM processor, for example. Having a major computer manufacturer switch to a completely different architecture is a huge deal because you can't take a program that was made for x86_64 and make it run on an ARM chip. Not without some complex software trickery going on in the background, and even that isn't guaranteed to get semi-decent results. That has serious implications. It can make cross-platform development rather complicated for software developers. It could break old programs. It could go very wrong if Apple doesn't handle the switch well. That said, I don't expect Apple to ditch x86 altogether because ARM isn't and cannot be a replacement to it. They'll probably release some low power macbooks with ARM chips and 500 hour battery lives, but no way they will move on to ARM completely. There will be Apple computers with the good ol' x86 chips."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hde7kf
|
How does an air conditioner cool the air?
|
Just wondering how my AC unit makes the air cooler in my room
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvkmc33",
"fvkn2dn"
],
"text": [
"When you compress a gas, it gets hot, when you expand a gas it gets cold. Your air conditioner compresses a gas so it's hotter than the outside air, then cools it down to the outside temperature, then brings it back inside and expands it, so it's cold enough to absorb heat from the inside air.",
"Usually a similar process to a refrigerator. Take a certain volume of gas at room temperature. If you compress that gas, you’ve moved all the heat energy in that gas into a smaller area, so it gets warmer. You have the same amount of heat, but in a smaller area. Now pass that compressed gas outside through a radiator (basically just a network of thin pipes that get heated by the gas as it passes through), removing heat energy from the gas, cooling it back down. This brings the temperature of the compressed gas down. When you bring the gas back inside, let it expand back to the original volume and you will get gas that is colder than the rest of the room. This cold gas can then be used to cool air passing through the indoor aircon unit, again using something like a radiator to let warm air in the room contact surfaces containing the gas. The gas warms, removing heat from the air."
],
"score": [
13,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hdhrhx
|
why do games sometimes have glitches where their characters bend and stretch in surreal ways, phase through the ground, or vibrate uncontrollably?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvl9uzz",
"fvliu2n",
"fvldpgf",
"fvlkofe",
"fvlsz4u",
"fvliift"
],
"text": [
"Difficult to say. A character could have thousands of moving points, all working together through calculations. There could be quite a few reasons why those calculations don’t add up at that point. Maybe there’s an undividable number for some reason, some programming languages have floating point errors (weird bug where the result of a calculation is actually incorrect), but also simple human errors. Especially in an open world where literally everything can influence the character’s movement, it’s impossible to cover every single thing. It’s also impossible to test every single thing, because very often it’s not a single action that causes a bug, but a string of subsequent actions. For simplification, imagine having 10 buttons, and 10 times you can press any button. That gives you 10^10 = 10 billion possibilities. That’s just 10 buttons and 10 actions. A game can have thousands of ‘buttons’ (things to interact with) and in theory an unlimited amount of subsequent actions.",
"There are lots of possible causes, but one is called an \"inverse kinematics\" glitch, the program is supposed to put someone's foot in the right place, and work out on the fly how to make everything else move so that it ends up working. But if it gets that starting place [wrong]( URL_0 ), then it can treat the parts of their body not like a real body, but like clouds surrounding bones that are like links of a chain that it's trying to tidy up into a line, even though there's not enough room to do that properly. So they end up overlapping with themselves and looking weird.",
"Programmers usually program rules for how things act and move instead of programming every little detail. If there's even small inaccuracies in the rules, our human brains notice pretty quickly. If they're not too bad, they usually aren't high enough priority to fix before the game goes out the door and that's when we see them",
"Long story short is that somehow somewhere a mistake is made. Typically it involves some failure for the model of the character and the math that determines how it behaves to cooperate. Most of these are some form of collision error. Basically things touching in ways they aren't supposed to. If it's falling through the floor that is either the floor not realizing it is supposed to be keeping the player out or the player character not realizing there is a solid surface beneath it. Similar with walls. Many things can cause this but the most common is some form of oversight where the floor isn't as whole as it should be. The vibration thing is probably two different positions sort of 'arguing' where the character is meant to stand. In certain situations a character can be in a position they aren't supposed to be and the game cannot get them out, sort of forcing the game to bounce them between the play area and out of bounds As for the weird stretching that is probably the game having issues where different parts of the character model being in different places than intended. The character is a bunch of number points so when the points aren't where they are supposed to be anything attached to them becomes warped.",
"Making a game engine is hard. It takes less effort and expense to *hope* that your physics simulation just works properly, than it does to include all the boundary checks and error-correction needed to prevent glitches from accumulating. The more objects there are, the more complex the interactions (collisions, friction, jiggle, kinematics, cloth, etc.), and the more often the state of the world needs to be evaluated, the more code and resources you need, and the more you'll have to pay for smart programmers and their time. Preventing ground phasing is easy when all you have to do is keep z > =0. But when your terrain is made of polygons, and there are instances where the character may indeed be underground, the game can break. This is also seen when characters phase through walls. Now you have three dimensions to worry about, with two dimensions being even more porous. Maybe the game figures that you were indoors all the while, even if there is no way into or back out of the building. And so may the game figure that you are below ground, and that gravity still works. Vibrations can occur when there isn't any dampening in the physics, or it can even be caused by the dampening system being given a bad state. Some other vibrations are due to NPCs having bad AI that gets stuck switching between two desired states. It may seem obvious to us that objects shouldn't fly off at 100 m/s from a minor impact, but not all game engines can set these sort of constraints. Some of the desired results may be at the very edge of a catastrophic, irrecoverable state. And some seemingly innocuous rules—like ensuring that no object may be within 1 meter of another—may backfire when corrections cause one of the objects to be launched at improbable speed. When you add multiplayer, you now have to account for all of the players having slightly out-of-date information from the server, which parts of the system you want to be handled by the server or the clients, and how to resolve conflicting data without resetting.",
"Sometimes the Animator or Coder puts the wrong Animation on the wrong virtual skeleton so the animations don't match with the bone configuration, making them bend and warp. I've done it myself many times."
],
"score": [
134,
44,
13,
11,
4,
3
],
"text_urls": [
[],
[
"https://www.youtube.com/watch?v=prJUQ3O95Go"
],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdj6ok
|
Why isn't it possible to create/program a non-pseudo random number generator?
|
I know about random number generators. In practice these are pseudo-random in the sense that they actually are not 'random' but behave like they are 'random'. This seems to imply that no non-pseudo random number generator exists. However, why is this is the case? Edit: Thanks for the replies! I wasn't aware of pseudo random number generators which really mimic randomness (while it is still debatable if it is truly random, but that's not what this question was about anyways). While somewhere in my head I knew that normal computer programs are just a set of instructions, I didn't see the connection between this observation and the question asked. Your replies made it clear to me, so again thanks for replying!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvligw1",
"fvlia91",
"fvllsdx"
],
"text": [
"Everything in computers is math. With math, put the same thing in, and you always get the same thing out. So as long as it's doing math, it can never make a truly random number. It can just do math to make numbers that look random. That being said, there are ways to put in a random thing and get random number out that way. For example, [one company has a web cam look at lava lamps]( URL_0 ), and feeds that into a psuedo random number generator, to get truly random numbers.",
"It is because these programs are made to run on a computer, and all computer code is a set of very specific instructions. This code is able to manipulate information, but it is impossible for it to create information. A true random number generator would need to generate numbers, but since a computer cannot do that it takes a seed number and manipulates it in a way that can make it seem random for whichever purpose it is needed.",
"There are methods of [\"true random\" number generators]( URL_0 ). I put it in quotes because there is room for debate about how truly random they are. They are random in the sense that it is unknowable to us what number they will produce, but the number they produce may be deterministic in some way that just isn't well understood to us yet. These number generators take special equipment that doesn't come standard on your average computer, so they must rely upon psudo random number generators."
],
"score": [
13,
6,
3
],
"text_urls": [
[
"https://medium.com/asecuritysite-when-bob-met-alice/the-wall-of-entropy-making-cyber-security-fun-f17c780bedc2"
],
[],
[
"https://physics.anu.edu.au/quantum/qoptics/random_numbers.php"
]
]
}
|
[
"url"
] |
[
"url"
] |
hdm7mf
|
How do 3D computer graphics render something that is smaller or thinner than a pixel?
|
I was reading about how ray-tracing works. As far as I understood, ray-tracing works by sending a ray from the "camera" for every pixel on the screen. The ray bounces off of surfaces and determines what color that pixel should appear. In this case, how would something that is smaller or thinner than a pixel be rendered, e.g., strands of hair? For example, if a CGI character is standing slightly far from the camera, then the strands of hair on their head would be thinner than the individual pixels on the screen. In this case, the computer has to render many strands of hair per pixel. How is such a thing possible with ray-tracing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvm13l3",
"fvmb7dk",
"fvmi4ui"
],
"text": [
"When rendering something smaller than a pixel, there are two choices, either pick an object that occupies that pixel space and render that color, or render that pixel as a combination of all the colors in that pixel. Most go with the latter. [Consider this image]( URL_0 ). There are pixels with the woman's black hair and the red background, so renders them as somewhere between black and red. From a distance, this looks like a smooth transition from her hair to the background. If they rendered the pixels either black or red, you start to notice the blockiness of the pixels, even from a distance.",
"If the ray for a given screen pixel exactly hits the thin surface, the entire pixel would be the color of the thin surface because that's the limit of the resolution. If it doesn't, then thin surface would be invisible (whatever was behind would be the one giving the resulting pixel color). A single ray per screen pixel is pretty terrible ray tracer, however. What actually is done is multiple rays are calculated for each screen pixel (offset slightly in the logical space of the scene, since you can have arbitrary precision there) and a composite of the results is used for the color. The thin surface is still kind of there, but only to shade the pixel a little making it visible when the image is seen as a whole.",
"First level, the math behind raytracing just spits out vectors (only information where an object is on a theoretically infinitesimal scale and in which direction it is pointing). On the second level a software will lay a grid with the screen's resolution on top and sum up the intensity of vectors crossing each pixel. The easiest way to visualize this is to open MS paint, pick the straight line drawing tool, choose the smallest linewidth and draw a line that isn't vertical or horizontal. press ctrl+G to show the grid and zoom in. You'll see that your line looks like a messy flight of stairs instead of a straight line. Mathematically you drew a straight line but every pixel it crossed was filled due to a finite number of pixels to display."
],
"score": [
43,
7,
4
],
"text_urls": [
[
"https://media.gettyimages.com/photos/pixelated-woman-picture-id600578849?s=612x612"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hdmqan
|
Does the electronic devices consume notable amount of electricity while on standby?
|
I've always had this doubt. For instance, while we're leaving a television switched off (via remote) and the main device is on standby (power light still lit up) will it continuously consume electricity? Or does it hold with the initial electricity it consumes while it's turned on? And also, I've connected all of my Pc peripherals along with the TV & router on a main port. So while I'm using only the WiFi, the TV & speakers were on stand-by everyday does it increase the power consumption??
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvm39bc",
"fvm5gno"
],
"text": [
"Yeah standby mode uses some power. It's vanishingly small compared to active mode though. I'd be surprised if it amounted to more than 3-5$ per year for all your devices combined.",
"They have to consume some electricity while on stand-by simply because they're not turned off, take for example a laptop on standby, some process of the operating system continue to run and work so when you re-open the laptop the pc doesn't have to re-run all processes like a cold start. Same things for the TV, when it is on stand-by you can restart it faster than if it was turned off. However like other just said consume is very very Low. I'm not sure I understand the second question but they shouldn't increase the power consumption"
],
"score": [
10,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hdqi62
|
What is the concept of hashtags?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvmlh02"
],
"text": [
"A hashtag creates something like a folder filled with photos, tweets, memes etc. that all have the same hashtag. It allows people to scroll through the sea of posts in a slightly more organised manner if they are looking for specific information. For example, if you wanted to read what people say or post regarding the Black lives matter movement, you could look up the hashtag #blacklivesmatter."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdsp1f
|
Why are TV screens measured diagonally and not horizontally?
|
Wouldn't it make more sense for it to be measured horizontally? It seems a bit easier.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvmxw2n",
"fvmyh53",
"fvnigz8",
"fvmyqgb",
"fvofmmv"
],
"text": [
"It would make more sense to have actual dimensions, but the goal is to sell a bigger and better product, not to be sensible. Since the diagonal measurement is the longest straight line on the screen, the companies use it as the standard to make their TV seem better.",
"From the invention of TV, the image aspect ratio was fixed at 4:3. Early TVs actually had round faced tubes, and the rectangular image was formed on them. The diagonal measurement let you give the size in one number rather than two, was functionally the same as people could divide, and made marketing happy because it was bigger than the other two and marketing thinks bigger numbers are better. Then came HDTV, and all the rules went out the window, but most are nor 16:9 and the old rules still apply. What irks me are '55\" class' TVs with a diagonal measurement of 53.6\".",
"The hypotenuse of a right triangle is a better measure of area than a height or a width. It also won't change depending on the orientation of the screen.",
"Because diagonal is a bigger number and makes you feel like you're getting something bigger. So for the producer it's a great way to not trick but make yourself look better but still tell the truth. It's marketing.",
"think of it this way i could sell you a 90\" tv but its only 2\"high if it was horizontal. or we would need two measurements to correct for this so a 90\"x2\" tv but then what comes first height or width? is it 90x2 or 2x90."
],
"score": [
82,
54,
9,
5,
5
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hdtbxs
|
How does the keyboard in Chinese language work?
|
There are a lot of Chinese characters. Altogether around 50 000. An educated Chinese person will know about 8000, and for reading a newspaper one needs to know 2000-3000. In Latin, there are roughly saying around 30 characters, so it's easy to fit them on a keyboard. How do Chinese keyboards work? Because I can't imagine how thousands of characters could fit on a keyboard. Thank you in advance!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvn2og5"
],
"text": [
"i've used chinese language settings before, you type the pronunciation (pinyin) of the words and it suggests phrases (hanzi) on the top of what you type that matches the pinyin. all you have to do is click the suggested phrase that you want to type! there are keyboards for touch screen phones and tablets that let you manually write the hanzi on your screen, but it's easier to just type the pinyin and pick the hanzi"
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hdtdxo
|
How does a computer control every pixel on a screen? Does the main CPU really generate a hex code for each pixel or is there something more clever happening?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvn4gf8",
"fvn2ixf",
"fvn7dce"
],
"text": [
"Computers work in binary. Hex is for human readability. But roughly, yes. In 24 bit color (which is what pretty much everyone uses today), you have a byte for red, a byte for green, and a byte for blue. So that means a number from 0 to 255 to specify the intensity of that component. And then you need however many pixels there are worth of those. So for instance at 1024x768 you need 1024 * 768 * 3 = 2359296 bytes for one screen. This is kept in the video card's memory, and periodically (usually 60 times a second) sent out to the monitor.",
"The GPU (graphics card) is tasked with figuring out the hex value for everything on screen. The CPU tells the GPU the positions of the things in the field of view and then GPU figures out whats in front/behind and what color each pixel should be. It then writes all of that into the \"frame buffer\" which is in the dedicated graphics RAM. Then that is read out every time its time to send a frame to the monitor which takes the incoming values and sets the intensity for each pixel There really is a large chunk of RAM that has the hex value for each pixel each time a frame is rendered",
"Originally, this was more or less the case. However, with increasing resolutions this would take more and more time from CPU. And contrary to popular belief, single core CPU can only do one thing at a time. So while CPU would be doing this thing, nothing else really would be registered. So you end up wanting special hardware to handle this screen pixel computing task. This is what GPUs are. So CPU can delegate tasks to GPUs. These tasks usually look like things where you can multitask, give each worker their own piece of data, like own piece of screen, and figure out what it should look like. So yeah, computer figures out hex values for every pixel, but this is offloaded to GPU these days as much as possible, as opposed to CPU."
],
"score": [
7,
5,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdx6zc
|
How does my phone know that an incoming call might be a scam?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvnqbxi",
"fvnrv2r"
],
"text": [
"because your phone reads the caller id and the provider has a database of scamy phone numbers. so it just checks the caller id against the database and tells you.",
"That might be your phone, it might be your phone company. Both have databases of bad actors and indicators of those bad actors. The phone company knows that the call with Caller ID saying it's from the US is actually coming as a VOIP call from the Ukraine. This is an unusual combination of call features. It might be nothing, but the warning tells you that the phone company doesn't have confidence in the call. As more deployment of STIR/SHAKEN takes place, there will be better cryptographic indicators to utilize in this way."
],
"score": [
17,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdygo6
|
What causes tasers to not set clothing on fire?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvo7enf"
],
"text": [
"How hot it gets from electricity passing though depends on how easy the electrons can go through the material. If it is easy for the electrons to go through they don't waste energy pushing through. If it's hard they waste energy and that comes out as heat. It is like when you're walking, on flat ground it is easy and you don't build up a sweat. If you walk uphill it requires more energy and you warm up. Since you're essentially nade of saltwater it is easier for the electricity to go through you instead of your shirt. Since it's pretty easy to get through your body up to catch fire. If you were to just zap it through the air and hold a shirt there the super heated air might like the shirt on fire. Not recommended without parental supervision though."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdyilh
|
How can most music that's playing from headphones have separate sounds for each ear?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvo0hwk",
"fvo0xbm",
"fvo113x"
],
"text": [
"Think of it conceptually similar to how music is recorded, with each instrument having their own channel (or often more, with the drum kit each drum and cymbal it’s own channel). When the song is mixed, these many input channels are then output to two output channels, a left one and a right one, each with their own volume balance per instrument, creating differences between the channels. Your music player can read this stereo format and then knows which channel to put to which ear, so a guitar solo could end up only on your left ear if the mixer/musician wishes to choose so. I believe most smartphones I believe also have a mono option which levels the two channels equally (or maybe just play one channel on both ears, I don’t know the details).",
"To play stereo, you need a headphone jack with two rings, that divide the metal connector into 3 sections. Two of those sections correspond to Left and Right. Some connectors only have one ring - they can only play mono (same sound to both sides). Connectors with 3 rings have a microphone channel too.",
"If you look at the headphone plug it will have little black lines around it... Those lines separate the signal into three pieces... there is a tip... then a ring... then the base of the plug or sheild. One ear gets its audio feed from the tip... the other is from the ring... and finally the shield is a neutral that helps reduce noise. If the original sound is recorded in mono it will send the same signal over both ear buds. If somehow you had a mono set of earphones (no ring) and the signal was in stereo... you would recieve the left side audio only over both earbuds."
],
"score": [
7,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hdykgh
|
What exactly is a buffer in Computer Science?
|
I've always been confused with buffer for I've heard the term in many realms including programming (nodejs) and operating systems; plus, "buffering" in video players. So, is it the same "buffer" everywhere? I mean is it a standard of some kind because it's been used in many technologies related to computer science.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvnz67s",
"fvo05a7"
],
"text": [
"Think of it like a temporary place to put things that need to be worked on or processed. Like a to-do pile of work on your desk. Instead of just doing work the moment it's given to you, you have people put it in a folder on your desk so you can work on everything at a steady pace. For videos for example, the rate at which you download a file may fluctuate but if the playback of that video did too it would be very awkward to watch. A buffer is a temporary storage place for some of that video so the downloading process can put it somewhere as it comes in and the playback process can play it at a steady rate.",
"It is a temporary storage of information. especially when you talk about realtime data tranfers so if there is any transmission problem the user will not observe it If you eat a chocolate bar each day you could purchase one each day but then you are out if you cant get to the store. If you instead have a buffer if 7 chocolate bar at home you can miss going to the store for a week and still have a bar to eat each day. That is what a buffer is, temperate storage of something. For video what you do is to first retrieve for example 10 seconds and then start to play. So if the network drops some packet with data you can ask for it to be retransmitted to fix the problem. IT can also be that packets are delayed or the rate you get them at drops for a few seconds."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
he2sjf
|
Why is Apple moving to ARM on Mac a big thing? My understanding is it will be able to run less software.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvor981",
"fvor6k7",
"fvorute"
],
"text": [
"There isn't actually anything stopping it from running specific software, the lack of supported software is simply less people write compatible software. And macs running on none Intel chips has been done before. They have previously used PowerPC processors which were developed by Apple IBM and Motorola. They were awful and as such eventually shifted to Intel. You will have performance issues here too as well as a long time for developers to move their software over. This will most likely not end well.",
"I frankly don't think that this will be a big deal, except maybe for some niche application that will never get updated and may have problems. They are going to do everything in their power to make this seamless, and developers will have ample time to make any necessary changes. The benefit of this is that the CPUs in use on the iMacs and Mac Books will be more similar to the CPUs in use in iPads, iPhones, and perhaps even Apple TVs or Watches. It will allow Apple to more closely merge the user experience between them, eventually making it so that your iPad doesn't feel all that different than your iMac, which will make switching between them far easier as time goes on. My Apple rep has told us that long-term, Apple's goal is to more or less merge the user experience between their devices, and this CPU change is just a step towards that.",
"Your understanding is not quite correct. It will require developers to release new versions of their software to run on the new chips. That doesn't necessarily equate to \"less softwate.\" This isn't the first time Apple has done this. They moved from the PowerPC chip architecture to Intel chips in 2005 and today Macs run more software than ever before. When Apple made that move, they provided a means for developers to build a \"universal\" app that would run both on PowerPC Macs and Intel Macs, and they've already announced plans to do that for the transition to Apple-built ARM chips. That's a transition strategy, and once most developers have made the leap to building for ARM they will eventually phase out the \"universal\" app and end support for software built for the Intel architecture. That will take several years. With the PowerPC-- > Intel move they maintained that transition stage for four years. From a business perspective, this is big primarily because it gives Apple more control over their hardware; they've been hamstrung by Intel on several occasions. Manufacturing their own chipsets gives them the freedom to move as quickly or slowly as they want/can without being beholden to a 3rd party chip manufacturer. They've already made that move on mobile platforms (iPhone, iPad, Apple Watch, Apple Home, Apple TV), and now they will have a unified chip architecture across that and their desktop operating system. That's potentially makes it easier for developers to build apps that cross mobile and desktop more seamlessly."
],
"score": [
6,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
he38rh
|
if a phone or other electrical device has a power saving mode, why would you ever disable it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvosren"
],
"text": [
"Depending on the phone and your settings, it doesn’t do certain things on the background. Things like frequently retrieving emails, automatically updating apps, background location services, etc."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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