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gdo86r
|
Purpose of TCP connections
|
There are 7 messages in total sent between the client and server, just to reliably send 1 packet of data. What is the use of each of these messages? Are they all necessary?
|
Technology
|
explainlikeimfive
|
{
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"Instead of looking at sending 1 packet look at how it works if you send hundreds or thousands of packet in a network where packets randomly can be dropped. There is not 7 packet of extra stuff if you send a lot of packets. There is packet to set up the connection and to close it down and occasionally reply to say do have received the data or for retransmission. Typical TCP has 1500 bytes packet and 1460 bytes of data. A 100 MB file is 100\\*1024\\*1024/1460=71820 packet. So if you use a few packets in overhead that's not relevant Dropping packet is not an error in a network but a feature because that is how you control the speed to match the slower part of the connection between the computer. If you do not what to set up a connection like that where the network stack handles the reliably delivery of data then do not use TCP. UDP has no overhead so you can just send a single packet. The problem is how do you know that is have reached the destination. That is now your problem to solve. For this reason when UDP is used when delayed packet are closed to worthless so in games and direct voice or video communication you set it up with TCP because it is simple and transfers the data as UDP. You then have the best of both worlds."
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3
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gdohkq
|
Does an Ethernet cord take from the same bandwidth "pool" as WiFi?
|
I'm trying to set up good internet for my family here during the quarantine, and I understand the modem but the router and bandwidth have got me pretty confused. Let's say for example my family has a 300mbps internet plan and I buy an "AC2400" router. 1) Let's say my ethernet cord is connected to the router and giving my laptop a speed of 300mbps. Does that mean there's now 2100 bandwidth "left" for wifi? Or is the 300mbps the ethernet cord is using separate, and there'd still be the full 2400 bandwidth left for wifi usage? 2) Also regarding bandwidth, does this mean that in theory *under perfect conditions*, 8 separate devices could each attain a speed of 300mbps? Just trying to understand how bandwidth works! Thank you for any help, it is appreciated!
|
Technology
|
explainlikeimfive
|
{
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"text": [
"That 2400 mbps refers to communications going to/from the router to any wifi clients. All clients, both wired and wireless, can't exceed the 300 mbps up/down speed *combined* for communications to the outside world.",
"All of your internet will still only have 300mbps. Your router can send and receive 2400mbps, to the WiFi and the Ethernet. If you wanted to send something from one computer to another on your “local” network, it could be as quick as 2400mbps. But, in communication to the outside world? That’s still throttled to 300mbps. That is shared between everyone currently using the internet in your home. It’s like having a water pipe coming in to your house, and the maximum it will deliver is 300 litres per minute. If you put an enormous pipe system inside your house that will cope with 2400 litres per minute, you can still only get 300 litres a minute into your house because that’s all that comes in. If you really want to speed everything up, you’ll upgrade the pipe coming into your house. (With your internet service provider). It’s not a perfect analogy but I hope it helped. Also, it’s probably 300mbps download & 50mbps upload. They’re measured differently and done by different parts of the system. Upgrading your router can make the internet it gets, get used more efficiently. But it won’t upgrade your max speed."
],
"score": [
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3
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|
[
"url"
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[
"url"
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gdpk6h
|
Why can a TV display different resolutions and still look crisp and clear, but on a monitor anything other than native looks terrible?
|
Technology
|
explainlikeimfive
|
{
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"fpjd231"
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"text": [
"Most TVs nowadays have all sorts of fun features that increase the output quality that your normal LCD panel doesn't. One big one I see in my house every day: My LCD on my laptop is 60Hz (it redraws the screen 60 times a second) The TV in my living room, however, is 120Hz, no matter the input. It can take 1080p, at 30Hz, and upscale it to 4K, at 120Hz. It's only slightly choppier than at 60Hz, and only if you're paying close attention. I play DVDs (480p) off of the playstation 3 (which upscales to 1080p), which displays on the TV (upscaled to 4K). All of this is brought in by one thing: The graphics card. The graphics card in my TV is amazing at upscaling, and antialising. The LCD in my laptop is being pushed by a graphics card that is only outputting a digital signal; it doesn't exactly know what exactly the LCD is looking for. It may \"support\" smaller resolutions, but the LCD is not meant to upscale on it's own, it outputs the data sent, and makes the best of it. The graphics in the TV, however, were tailored to that screen, it has a pretty awesome idea of what the end result is supposed to look like, and takes whatever input it gets, and makes it what it should, your LCD does not have this feature, and neither does mine. & #x200B; TL;DR: Your TV usually has a computer of some kind that makes whatever input being fed into what it knows it should be, while the LCD panels on laptops usually are only made for one resolution, and is not mad to upscale smaller inputs on it's own."
],
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4
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"url"
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[
"url"
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|
gdpnhr
|
How does storage on phones and computers actually work, and why is there a limit?
|
Technology
|
explainlikeimfive
|
{
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"fpirla4"
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"text": [
"Modern phones and computers use \"Solid State\" storage. It works basically by charging super tiny parts (called floating gate transistors) in the solid state drive. These parts hold a charge, and the drive scans to see if the parts are charged (0) or not charged (1). This is binary storage, since all computers run on binary, which is just a very fast input of 1s and 0s. You run out of storage because these transistors, small as they may be, still take up physical space. You can cram terabytes into a very small space, but this is incredibly expensive and most people don't use enough storage to make this worth it. Some computers still use a \"hard drive\", which is a series of disks with small magnetic particles in them. When writing to a hard drive, a magnet sends specially timed charges to the disk, which then change the magnetic orientation of the particles, and when reading, it detects which ones are magnetized one way (1) or another way (0). Again, it's binary. A hard drive requires spinning discs so it takes a while. SSDs do not require anything moving so they are much faster. So the even more boiled down answer: A small piece of physical space is either electrically or magnetically designated 1 or 0, which the computer can read and turn into an image on your screen. You run out of space because these small pieces are expensive to make and take up room.",
"All data is converted to a series of 1’s and 0’s for computerized systems to read. Phones and PCs store these 1’s and 0’s on chips and drives by writing them down and reading them. Just like a chalkboard there is only so much space to write before it’s full."
],
"score": [
15,
3
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[
"url"
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[
"url"
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|
gdqbrl
|
Why is it not recommended to have 2 antivirus programs running at the same time?
|
Technology
|
explainlikeimfive
|
{
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"fpiv89l",
"fpjc21e",
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"text": [
"Antivirus 1 checks something. Antivirus 2 sees Antivirus 1 is doing something and checks it. Antivirus 1 sees Antivirus 2 is doing something and checks it. Repeat. Both Antivirus 1 and 2 are involving some serious security critical things, so they both read it as something that really needs to be checked.",
"When the computer starts, the antivirus software stands guard at the over everything, like a bouncer at a club. There's only one place a bouncer can stand, and if you try to put two there, they will fight for control of the bouncer position, and don't let anyone in or out until they settle their feud over it, and the club, being the computer, has to wait for all of this before the party an start. In some cases, both bouncers knock each other out and the club shuts down completely. Source: 15+ years IT, with a fondness for cyber security + a 4 year old at home",
"One anti-virus, which is the one built in to windows, is all you need. Anything more is excessive and will slow down the system while hounding you with advertising, all while doing a worse job than the free windows defender that comes with your operating system",
"You know the spiderman meme where there’s two of them pointing at each other? Basically that",
"The same reason you don't have 2 chauffeurs. They fight over the wheel and eventually your car is gonna hit something.",
"Specifically, the advice is not to have more than one anti-virus tool actively protecting your computer. The reason for that is because active-scanning AVs detect when the operating system reads or writes files, and scan those files. So each time you read/write a file, you've got multiple AVs fighting over who gets to access the file to scan it, on top of whatever original process was trying to open the file (eg. Word for a document). At best this causes poor disk I/O performance. It can also cause deadlocks (two processes waiting on each other for file access). AVs also scan processes running in memory. It's possible the AVs will try to scan each other, and maybe fail because AVs tend to run with special OS privileges that make it inaccessible to other software, but that's never been a problem in my experience."
],
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"url"
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[
"url"
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|
gdw81s
|
how come a pc needs a big stick of ram to fit 8gb but a phone can have the same amount in a much much smaller space.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpjtjvo",
"fpju6mw"
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"text": [
"1. The (larger) PC RAM is generally cheaper to produce 2. Physically larger RAM has larger surface area and is therefore easier to cool 3. The smaller RAM such as found in phones generally has to be soldered directly to the motherboard, and so is not replaceable/upgradable.",
"People are hitting at the 2 best answers here but I wanted to consolidate and declare them at least once. One answer: because they can. A PC has real estate, and a traditional motherboard with DIMM slots can fit easily in a larger footprint, and be easily interchangeable. The second reason: bandwidth. There are many robust connections on a ramstick, similar to PCIe, because outside of the CPU that is the fastest format we’ve found for connecting components: aligning them together in a slot. And you can’t fit too many CPU sockets on a motherboard. You want to shrink RAM? There’s a nice hot swappable format called SO-DIMM that is essentially a bigger stick in a smaller form factor. The issue is that the connections aren’t quite as numerous typically, the connector isn’t quite as robust, ECC and registers are commonly omitted, and ultimately SO-DIMM isn’t rated for the same kind of speed. You’ll notice as you continue to shrink you’ll lose out on more and more of these feature sets unless you trade a swappable part for solder. At that point you gain freedom in what’s typically a much smaller piece custom-built for that need, but unless heavy manufacturing went into it even this soldered component won’t compete with a DIMM stick simply because the market isn’t quite there for that kind of performance or reliability."
],
"score": [
16,
3
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[
"url"
] |
[
"url"
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|
gdwqjy
|
Why is Gain Staging used in Electronic Dance Music?
|
Technology
|
explainlikeimfive
|
{
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"fpjzbg1",
"fpkd0kz"
],
"text": [
"Gain staging is a fundamental part of every type of audio recording and playback. Basically, imagine your audio signal is water through a hose. Next, imagine there is a spigot (gain control) every 50 feet, and you can’t turn them up too much or the hose will leak and lose “signal”. When a preamp or amp is overdriven, fidelity is lost. The idea is to use each component within its specifications in order to get the cleanest audio, or to use distortion to your advantage through types of clipping and distortion that are pleasing to the ear, such as harmonic distortion achieved with tube amps.",
"Well, it doesn't really. With the advent of the digital floating point system, gain staging isn't nearly as important as it was in the analog days. I remember seeing an Avicii video where he was clipping the master buss like crazy. I still do it though, because it helps with consistency when it comes to things like presets."
],
"score": [
4,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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|
gdyt1q
|
how does a search engine search the entire internet in a couple of seconds?
|
Technology
|
explainlikeimfive
|
{
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"fpk8dw9",
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"text": [
"It doesn’t. It searches an optimized index that the search engine company has carefully built over a long time. Instead of driving around the neighborhood making a list of all the businesses, it just looks in the phone book.",
"they actually dont. they have these \"robots\" (well, programms) that constantly check the web and then save certain infos (keywords) at the server park, where the \"search engine\" is located. this happens all the time and is independent of you searching something. so all that this search engine does when you start a search is ask its local computers (servers) \"have you got anything related to this search\" and then the servers check their data for keywords and those results are then grouped/ordered and presented to you as search results. this way it doesn't have to check the entire internet and just checks what it has already there, making it so fast. the \"skill\"/usefulness of the search engine is determined by how well it's keyword-catalogue is maintained and by how well its sorting algorithms present you those results. does this answer your question?",
"There are different methods used by different search engines but this will I hope to clear some of it up. Search engines don't search the internet, they search their own internal data source, they have some programs that look at all the pages and then put a reference to the page in an internal database. this is refreshed from time to time and even in some cases stores the previous version of the page. While they are building up this they can then see how many other pages point to a page/site the more pages that link to a site pushes up the result in the page but there are many other things that do that also",
"For instance, Google uses web crawlers, that identify all links to pages, to help generate its search results. Google has a huge index of keywords that helps determine search results. Google also has an algorithm which assigns each web page a relevancy score. The higher the score, the most likely the page will show up first, depending on what you are searching for."
],
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474,
35,
7,
3
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"url"
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[
"url"
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|
gdz9oy
|
Why do old jazz recordings sound better than other records that have been released later on?
|
It seems to me as if most jazz records of the 50's and 60's sound way better in recording quality than most of the other music at that time (e.g. blues, country, rock, etc.) or even later on. Why is that?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"text": [
"**Why do they sound better than most of the other music at that time?** Jazz music, including its crooner singers and big bands, was some of the most popular mainstream music at the time. As a result, they had more budget and resources for good recordings. **Why do old jazz recordings still sound better than newer music?** From a music perspective, many of the musicians who were playing on the jazz records of the 50s and 60s were seasoned live performers and session musicians. The way records were recorded back then involved the whole band to be in the same space performing the music. As a result, a lot of these musicians had lots of experience and good chemistry with each other, which meant they could groove better and bounce off each other musically. In later times, as studio technology evolved there was less of an emphasis of capturing the perfect recording of the performance in the room, as session musicians could be swapped in and out and record on completely different days, multiple performances could be cut together and edited to fix mistakes, etc. Some people would regard say that as a result, some of the soul and imperfection was removed in favour of higher fidelity and perfect performances. Speaking of music technology, the actual equipment was very different in the 50s and 60s. Because they couldn't record lots of microphones at once, often bands would have to perform around one or two microphones and members would have to physically move back and forth in the room to adjust their volume. This made the sound of the room a very important basis of the sound. Modern recording methods favour multiple microphones allowing for the complete isolation of each member of the band, meaning that only the pure instrument is captured, allowing for greater fidelity, but without the character of the shared sonic space being in the record.",
"Saturation from the tape recording mediums of the time. It adds warmth and character. Even today during mastering you might do a pass through an analog tape machine to get the same result.",
"So people have been mentioning the technology and budget difference, but also, Miles Davis and John Coltrane were doing crazy crazy crazy music theory. URL_0 This explains it well. Tl;dr: they would tune the entire piano for the specific tonal sounds they needed for just one chord at a time. For every. Single. Chord.",
"1. Firstly, ask yourself whether you aren't picking up on the fact that 60s rock sounds *bad* to you because it differs from how modern day rock music is produced (whereas jazz remains mostly unchanged). 2. Secondly, are you thinking of smaller ensembles? Have you checked Elvis against a big band recording of the 60s? That could be a reason. 3. Barring that, what you have is typically a small ensemble of top musicians playing live in a good room and a couple of good microphones pointing at them, set up to best capture the natural sound event happening. Much easier to make that sound good than Sgt. Pepper, which is the product of countless overdubs, tape splices, bounces from one tape to another causing a degrade in quality, the ample \"artistic\" use of effects and production tricks. 4. Rock records were (and are) recorded and mixed for kids with cheap mono portable stereos, making close miking predominant and sharp equalisation to give the sound \"punch\" on a small box (compare: the loudness war and iPods today). Jazz albums were and are recorded to sound natural and as close to the real acoustic event on a proper pair of speakers as possible."
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[
"url"
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ge1ppa
|
How do computers understand programming languages?
|
So I just got into learning JavaScript, and I wanted to know how complex commands are translated into the binary that computers use. Also, how do computers know that a certain string of ons and offs from their transistors mean a certain command, even abstract ones like loops and logic?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"ELI5 that concept is challenging. But essentially the Javascript you're writing gets interpreted into another few languages before actually becoming binary code. Binary code is a representation of what is actually occurring in the physical level of your computer. Conversely, the physical component of your computer represent logic structures (if, and, or, etc.) can be translated into binary and move back up through to your Javascript code. This is an odd idea to explain simply to be honest, bit that's the gist of it. I would look into assembly languages of you want to learn more",
"I recommend the 'Building an 8 bit computer' Youtube series by Ben Eater. He goes through step by step how a computer works all the way from how electricity flows around the components to how programming languages get translated down to assembly and the resulting physical steps in the computer.",
"\"understand\" is wrong word. The CPU circuits only execute commands. Each command is a combination of electrical signals on a set of wires. The output of that signal on the wire leading to the logic circuit is a new set of signals on a different set of wires. It's not really understanding or interpreting. It's just passing electricity thru circuits to come out as other electricity.",
"It's simple, somebody wrote a program to read the script (it's just a text file), parse it to see what you ask (most of the time: call this function on those arguments), then lookup the CPU instructions for that function, run that, then read the next thing. It's what we call an interpreter. All this works because your CPU has an instruction set (most probably x86_64) which is in binary, and all you need to do is \"execute\" it by telling the CPU to jump at that address."
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17,
3,
3,
3
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"url"
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[
"url"
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ge2suu
|
How does an EMP actually work and how can it affect people with pacemakers?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpkwc7n",
"fpkya57"
],
"text": [
"An EMP causes currents in the electronic circuits it contacts. Pacemakers are very sensitive, because of how they are hooked to the body, and so messing up the circuitry could be bad.",
"An EMP device / bomb will create a sudden electromagnetic pulse. It works because every wire can be an antenna, the electrons inside the metal (atoms) in the wire can move, and create electricity, if there's an electromagnetic pulse 'in the air'. That's how antennas work, the radio station antenna creates electromagnetic pulses (at the radio frequency), and any metal wire (receiving antenna) in range will pick up a corresponding pulse of electricity. This phenomenon is called [electromagnetic induction]( URL_0 ). The pulse from the EMP is just stronger than your typical radio station, so the voltages created inside the electronics wires are strong enough to fry the electronics. The pacemaker would short itself out and stop working. The way to protect against it is with a [Faraday cage]( URL_1 ). If something like a computer has a metal case, and it's grounded via the 3rd prong of the power plug, that's a Faraday cage. Electricity follows the metal and discharges to the ground, instead of \"getting inside\" the cage."
],
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6,
4
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"https://en.wikipedia.org/wiki/Faraday_cage"
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"url"
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[
"url"
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|
ge3aob
|
Why does pluto appear red/white in fairly recent photo's, while in a picture of 2003 it seems yellow/green, and in a picture of 1996 it appears grey?
|
I can't post a picture here, so it's slightly hard to describe. I just saw a picture of pluto in these different years, and the colors change so much! I've got two theories: 1. Is this because the first camera could only do black and white, the second one could only do yellow and green and the newest one can do a ton of colors? 2. Is it because we see a different side of pluto? Or maybe a sun is shining weirdly on it? My theories are probably wrong, I think, but those are my thoughts...
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpl0wth"
],
"text": [
"You're comparing very, very different things. The red/white image was taken from right next to Pluto with a camera that flew all the way out there on the New Horizons spacecraft. It's a B/W detector with color filters that allow it to make full color, properly corrected, images. The 2003 and 1996 images are Hubble Space Telescope pictures, taken from near the Earth. That's a super-long way from Pluto. The HST is also a B/W detector with color filters. There is some great work done in color correcting HST images, but those algorithms require more data than a 2-4 pixel wide image can give. Pluto was a little closer in 2003 so there is a little more data, but the most yellow pieces are edge pixels where the information density is the lowest and the uncertainty the greatest."
],
"score": [
3
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"text_urls": [
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|
[
"url"
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[
"url"
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ge8jg5
|
What do 7,500 people do for Airbnb?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpm5k6l",
"fpmz9cq"
],
"text": [
"Web devs, business, corporate, legal team, customer support, marketing, etc. For multiple countries around the world",
"So many people speculating here. You can find their actual org charts and hiring breakdown pre-IPO here: [ URL_0 ]( URL_0 ) One thing that stands out is that they have teams around the world. Every country where they have a presence, they need marketing, legal, customer service - and even sometimes engineering, if the needs for the web site in that country are so dramatically different."
],
"score": [
29,
6
],
"text_urls": [
[],
[
"https://www.cbinsights.com/research/airbnb-strategy-teardown-expert-intelligence/#organization"
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|
[
"url"
] |
[
"url"
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|
ge8tqh
|
Why did it used to take so long for a film to come out on video or dvd after it stopped being played in cinemas.
|
I read it was the rise of bootleg copies of films that made the film studios release them quicker to video but I remember it could be up to a year between a film being in the cinema and then coming out to buy but I never could understand why.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"fpm2zak"
],
"text": [
"Windows. There's a preset window between the last theatrical release and either PVOD or streaming services. It used to be over 90 days but the studios have been shortening it little by little and now it can be between 45-90 days. Cinemas have a fast high return (most of your ticket money goes back to the studios). NATO (National Association of Theatre Owners) is basically the cinema owners lobbying group and they try to keep the window as wide as possible because it means more money for the cinema, but sales have been declining for a while at the cinema and studios want more ways to make cash so they shorten the window. Cinema owners push back and it starts a fight. In today's news AMC boycotted Universal because they basically took that window to 0 (usually 90+ days). Since AMC is a huge player, universal may bow to AMC. It's a whole thing. Source: was a cinema manager and corporate finance for cinema chain.",
"This other response is great, but it might not be an ELI5. The ELI5 is more like - to protect the profit of the theaters and then cable TV. If a movie was good, then people wanted to see it. An agreement made it stay in the theaters for a while to generate profit for the theater. Then eventually it would go to HBO (or Showtime or whatever) for a while, so they could make money. Then it goes to home video. So, this is all about protecting profit for the middle men between the producer and consumer."
],
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12,
5
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|
[
"url"
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[
"url"
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ge9986
|
When you search something on Google and it shows a sample in the results page, how do you locate that when you follow the link?
|
Oftentimes I'll go to that page and it's either a mile-long text or a PDF and I have no idea where the needed portion is.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpm2cz8"
],
"text": [
"I just use ctrl-F with what I saw in the preview of the page, but yeah there has to be a better way."
],
"score": [
5
],
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|
[
"url"
] |
[
"url"
] |
geaq1p
|
How does holding the power button down tell a phone to turn on when it's off?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpmc4rr"
],
"text": [
"Computers these days are never fully \"off\". The screen is off and the operating system isn't doing anything, but as long as there's still power there's a closer-to-the-metal operating system that basically just keeps the clock ticking and listens for you to hit the on key."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gedwxn
|
5G: generation or frequency/bandwidth?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpmvel0"
],
"text": [
"5G does use different frequencies. That's the kernel of truth behind the hype. There's nothing to worry about, though. The frequencies are non-ionizing radiation, so they're safe."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
geejv7
|
What happens when we remove a USB stick unsafely?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpmzmkc",
"fpmz9qz",
"fpnspyg"
],
"text": [
"You risk interrupting an operation in the middle. Think of say, yanking somebody's notebook from them without asking. Maybe they were already done with it, so nothing happens. Or maybe they were in the middle of rewriting everything, in which case things get lost. In general, these days systems count on people not complying with this rule all the time, and try to minimize the damage. But that doesn't mean damage can't be done. If you're doing something important, like say, giving a talk in front of people and were copying the presentation files to the drive, there's a chance you might find out it's not working when you put the stick in your laptop when on the stage. So best to make sure to do it the right way.",
"It depends on what process you’re in. If you’re transferring data, and you unplug without ejecting first, your data may become lost or corrupt. If nothing is going on, it’s usually safe to remove a usb, but there’s no reason to risk it. This is similar to shutting down your computer vs just turning off the power. The shutdown process gives your computer a chance to save work and tell all the programs to stop doing anything. It’s always better to tell the computer what you’re doing before you do it.",
"These days, very little. Ejecting it properly ensures it’s not being used in any active operations, but most modern computers will usually keep your USB safe even if you don’t properly eject it, unless say you unplug it when actively transferring files between it. That said, while it’s usually safe, eh, it’s a good habit to get into, and it only takes a second"
],
"score": [
26,
5,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gefhp6
|
How are older pictures colorized?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpn59of",
"fpn9i50"
],
"text": [
"There are some algorithms/AIs that can do this, but usually it's done through hours and hours of work, by hand, in Photoshop or equivalent. [Here]( URL_0 ) is an example.",
"Research can tell what color certain items and articles of clothing would likely have been during the time period. So context clues mostly."
],
"score": [
13,
3
],
"text_urls": [
[
"https://youtu.be/C2Srw245R7U"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
geh75x
|
What does hardware-based platform mean in programming?
|
How does hardware based platform work and how does it differ from platforms that are independent from the underlying hardware like Java?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpnhc1x"
],
"text": [
"It means the program you are creating is targeting a specific piece of hardware, and won't work on anything else \\*. For example if you're making a PS4 game, that game will only work on a PS4. If you want to make it work on Xbox, you have to replace some of the code with Xbox specific stuff, and recompile it for Xbox. Compare that to Java, where a Java program can work on different types of hardware as long as they have a version of the Java runtime. It can run on a standard x86 based PC, but it would also work on a machine which has a different type of CPU and/or OS. The Java Runtime handles all the stuff that's necessary to interface with the hardware and OS, instead of your program doing it. You don't need to make separate versions for those platforms. \\* Unless that other hardware has specifically been designed to support software for an older platform, e.g. PS5 will run PS4 games."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
gephlb
|
Why is there a lot of talk about Apple moving to ARM chips and therefore software having to be re-written/updated. Why do apps care if it’s an Intel chip or ARM?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpote0x",
"fpost3p",
"fpp7czq",
"fpoz1zw"
],
"text": [
"the instruction sets of x86 and ARM are different. imagine if you had a cookbook in English but your user speaks Japanese.",
"Imagine you're in the business of custom modding motorbikes, but suddenly all your customers have are jet skis. The way an x86-based (Intel, AMD) CPU and an ARM CPU works internally is completely different and neither can run stuff made for the other without some patching and a full recompile.",
"To add a bit more detail to the answers here, x86 has more \"words\" in it that tell the CPU to do more things using less code, which was important many years ago when CPUs couldn't \"read\" words very quickly. ARM was designed to have fewer \"words\" that can be \"read\" very quickly, but more complicated tasks have to be written using more \"words\" now. For example, x86 has entire sets of \"words\" dedicated to converting binary numbers into decimal numbers. While a program written in x86 could use a single \"word\" for this task, ARM code would require multiple simpler \"words\" to do the same thing. Because ARM decided to get rid of all these extra \"words\" and focus just on \"reading\" simple \"words\" as quickly as possible, the physical CPU is much smaller and requires less electricity to run. This is attractive to apple who wants to make their laptops thinner *and* have the battery last longer.",
"A CPU has a bunch of electrical pathways that implement their features. So if you want to add two integers together, there's an electrical pathway to do that. There are also electrical pathways for selecting which electrical pathways you want to use. So you have some data sitting in the input circuits of the CPU, do you want to add those inputs or multiply them, etc? Our computers are all binary bits and electrical pathways, and we can describe those bits and pathways as numbers. In other words, the list of pathways you can select from are enumerated, and we call those members of that list \"opcodes\". Your programs are just sequences of opcodes. So add is 1, multiply is 2, load is 3, store is 4... And your programs are just 1234... Obviously there's more to it than that, but not relevant to ELI5. The thing is, There are an infinite number of ways an engineer could make a CPU add. Which way they chose has significant consequences. Also, not all CPUs have the same operations, not all chipsets implement those operations the same way, not all chipsets enumerate those operations in the same order. There are other considerations at this very low level. Many of these considerations have to be taken into account when you translate source code - which is a human readable (to the trained eye) text document, into a binary object that can run on that hardware. We call this \"CPU Architecture\". And a program for one operating system, for one architecture, would be utter nonsense on another operating system or architecture. That means you need to re-translate source code to the new target. That's not as trivial as it sounds, as source code isn't necessarily portable. Developers may have accidentally or explicitly taken advantage of knowing their software targeted a particular OS or hardware, and now those assumptions need to be revisited, that source code will have to be rewritten. It takes time, and is error prone. The consequence can actually be very dire, making porting effectively impossible in some instances - sometimes a port is effectively a complete rewrite, if the assumptions exploited were damning enough."
],
"score": [
12,
6,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
geqxyq
|
When/Why are cookies necessary?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpp1kn9",
"fpp17y4",
"fpp21nm"
],
"text": [
"The Good: I know that it helps remember your settings and your login. So for example on reddit, it keeps you logged in. I think for reddit, though, settings are kept with user profiles rather than with cookies? The Kind of Bad: Cookies are used for online advertising, like Google Adsense. Companies make money off of online advertising on their website and aside from subscriptions/direct payments, this is how they stay afloat. The Bad: This means that they track you. Like Google tracks your online behavior across websites to better gear advertising towards you. Even if you have adblock and you can't see the ads, they're still doing this. So what do you do? You can use extensions, search engines, and browsers that help you avoid unnecessary cookies. Like the ghostery extension, duckduckgo, and the Brave browser (built on Chromium) or Tor.",
"It stores pretty much all the data. Like, what language you view the site in. Are you logged in or not? Pretty much anything the site knows about you uses cookies. Not all cookies are trackers.",
"So: HTTP is a sessionless protocol. Basically, the server has no (decent) way to identify that two consecutive web requests came from the same computer or not just using HTTP. So cookies were created, which are bits of data the server tacks onto the webpage it sends to you, and your browser automatically sends them back with the next request to that webserver. This way the server can tell the client to hold onto a little name tag and flash it whenever it shows up again. Very convenient! It's used to store logins, back in the day it was used to store cart contents in webshops (that mostly switched over to being stored serverside with your account data) and lots of other stuff."
],
"score": [
6,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gev7wi
|
Server racks, is one rack on the shelf sort of like one individual computer?
|
* Can that one rack (or is the rack the container and each computer is a blade?) be disconnected from the shelf and plugged into a monitor and keyboard? * for each individual rack on the shelf, can it only handle one user? Or could one CPU handle one user per core or is it even multiple users per core? * in the instance of a video game server, does the server run a virtual machine for every player and each CPU can handle several virtual machines?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fppsl9x"
],
"text": [
"A server isn't all that different from any other ordinary computer or laptop. A \"rack\" is just a standardized shape and size to allow multiple devices to fit in a known measured amount of space and mount up to the rack's frame. A \"rack\" is (typically) 19 inches wide, and its height is measured in units of about 1.75 inches tall. So when you order a server that's \"2U tall\" you know exactly how much space it occupies and whether it will fit. Installation and removal involves sliding it in/out from the 19\" wide front typically and (un)screwed it to hold it in place. The server itself follows the normal rules of a PC. You can install Windows or Linux (or other stuff) on it, turn it off and on, and all that good stuff. You can install any software you want and run it normally. It will have power supplies, network port(s), USB ports, display connector of some kind (VGA is still common here), etc. But with [a stack of 30 of them all looking the same]( URL_0 ) you might have to consult the labels to figure out which is server #17. Some designs get creative. I've seen some where a single slot \"computer\" actually has 2 motherboards in it and so is really 2 computers, but that means it needs 2 network cables, etc."
],
"score": [
5
],
"text_urls": [
[
"https://docs.oracle.com/cd/E19471-01/819-5347-12/819-5347-12/c~sgrs1_ov_locate.htmlc"
]
]
}
|
[
"url"
] |
[
"url"
] |
gevcxd
|
Why on computers if you highlight text and then push caps lock it doesn't turn the highlighted text into uppercase, but if you highlight something and click delete, it deletes it??
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpptdau"
],
"text": [
"Caps lock works on the next value you put in, delete on the previous. Protip: shift + F3 does do what you want. Convert lowercase to uppercase."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gevv01
|
What is Roko’s Basilisk in the simplest terms possible?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpq84ph"
],
"text": [
"\"Roko's Basilisk\" is the name applied to a thought experiment suggested by a user who posted on a particular message board using the name Roko. This experiment is notorious because it imagines a hypothetical future which could imperil the thinker merely by knowing about it. People who find this suggestion plausible would consider the knowledge itself to be inherently harmful, so by asking to understand this better, they would argue you are harming yourself; they could argue that I'm trying to injure you by explaining this idea. For this reason, if you feel knowledge can be inherently dangerous, if you are scared of the potential power of artificial intelligence, or if you think counsciousness could exist in a purely virtual environment (such as in \"The Matrix\" or similar works of science fiction), I think you may not want to read the rest of my comment. The specific idea Roko proposed went something like this: > !suppose that there existed an AI of such incredible power that it could gather enough data about the state of the universe to perfectly recreate an artificial model of everything that has existed, right down to a simulated consciousness for any person in history. Such an entity would be indistinguishable from a god, for our purposes. Suppose that it was so malicious as to require anyone with the ability to imagine that it *could* exist to spend their lives working *to bring about* its existence, and if they don't, it can bring a digital form of your consciousness with all your memories and beliefs and behaviors to existence in its digital environment and inflict upon you whatever version of hell would be most horrific. With its perfect knowledge of history, this malicious AI god knows that you're now aware of its hypothetical existence, and unless you now devote your life to helping advance AI to the point that this AI can finally spring into existence, there is now a possibility that, some time after your death, an AI god wills you back into simulated existence to punish you for that sin.! <"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gew22f
|
What causes Wifi signals to fluctuate (ex. Strong to weak signal)?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpq07lo"
],
"text": [
"WiFi signals reflect (at least partially) off lots of surfaces inside buildings. These reflections bouncing around can interfere with each other, in some places they add constructively and others they cancel out. Since the wavelength of WiFi is somewhere around 10cm, these interference patterns can be very dense -- moving your phone several cm can be enough to move it from somewhere where reflections are cancelling out, to an area where they aren't. The wifi signal frequency also hops around slightly, which means the wavelength changes constantly and the interference pattern fluctuates a bit. Usually the line of sight path to the router is much stronger than any of the reflections (unless there is a large metal object near the router), so this effect isn't noticeable close to the router. If you move to another room where the direct path is weakened through a wall or floor, you're much more likely to experience signal fluctuations."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gewrer
|
if network TV can be broadcast over the air for free, then why cant WiFi be a tv channel (so it’ll be universally available and free)?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpq21t2"
],
"text": [
"TV broadcasts are the same no matter who is receiving them (assuming they are in range), and one directional (the viewer isn't sending a signal to the transmitting towers). The same is not true for internet connections"
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gf1bb3
|
- Why do cellphones that are very small seem to have specs that rival much larger PCs?
|
I'm not saying top end PCs, but a lot of cell phones seem to have incredible specs in such a small package, 8gb ram and processors at around 3ghz?, in such a tiny device? How is that possible? The only thing I don't think they have is Graphics cards, is there a difference in 8GB of cell phone RAM and 8 GB of PC RAM? Or 3ghz in a cell phone vs 3ghz in a computer? Are they actually on the same scale?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpr1eh8",
"fpqyien"
],
"text": [
"The ram is roughly the same as in a PC, but mobile processors are far less powerful. The GHz of a processor just tells you the cycles per second, but not how much work is done by each cycle. Imagine you've got a kid with a spoon and a bloke with a shovel, both digging once per second; they're both going at the same 'speed', but going to shift vastly different amounts of dirt.",
"> Or 3ghz in a cell phone vs 3ghz in a computer? Yes, the [megahertz myth]( URL_0 ). The 3ghz simply means the CPU's clock speed, but it doesn't say how many clock cycles it takes the CPU to complete each operation. If one CPU runs at 1ghz but can complete an operation in 3 clock cycles, it will be much faster than a CPU that runs at 3ghz but takes 20 clock cycles per operation."
],
"score": [
90,
17
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Megahertz_myth"
]
]
}
|
[
"url"
] |
[
"url"
] |
gf2ku4
|
How do touch screens know the difference between your skin and any other object?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpr28h8"
],
"text": [
"Anything that conducts electricity can be used as an input for touch screen (so the screen never really knows if it's your skin or another metal) When you wear gloves, you are not able to usr me it because gloves are not conductor"
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gf514s
|
How does bluetooth work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fprkpy5"
],
"text": [
"Imagine a cord between two devices, but rather than a cord, it's radio waves constantly being emitted by a chip inside. These radio waves have a relatively short distance, as opposed to, say, the radio waves you're emitting while making a call of some kind, but still the same concept. Kinda just phone calls on a much smaller scale."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gf5qv3
|
Why can’t my laptop microphone pick up the sound coming from my laptop speakers?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fprj22w",
"fprlgn9",
"fprixv5"
],
"text": [
"There could be a few reasons for it. Most likely is that the laptop is programmed so it knows what audio it is outputting and can isolate and remove it from what the microphone is picking up. Another possible factor would be the type of microphone it is. Different types of microphones have different areas around them where they pick up sound. So your laptop could have something like a cardioid mic which mostly picks up sounds in front of the mic. I believe most laptops have condenser microphones though which tend to capture sound from all directions.",
"It can, and it does. But both the hardware engineers who built the laptop, and the software engineers who write video conferencing software, work very hard to make it all work. The location and design of the microphone is done to reduce the amount of sound picked up. They often have multiple microphones, and use them to detect the direction the sound is coming from, to try to reject sound coming from the direction of the speakers. Some systems even subtract the sound from the speakers from the sound picked up in the microphones, in the same way that noise-cancelling headphones work. Another trick is to filter knotches out of the speaker sound, and then use a complementary filter to filter out 'opposite' knotches out of the microphone sound. This is quite effective, but produces a distinctive 'twinkling' distortion to the sound that you have probably heard on some video conferences. Also importantly - conference apps never feed your microphone sound back to you. But the sound of your voice will go out of someone else's speaker, into their microphone if their setup is bad enough, and then out of your speaker into your mic, causing problems. But often you will not realise this, even though others can't hear you, because the system is dialing down your volume and distorting all sorts of things to prevent the system howling. The take away - your computer is working hard to try to reject the sound of the speakers, and is destroying the sound of your voice to do it. So do everyone a favour, and use a headset!",
"It can. On zoom calls I play recording videos all the time for my team and just disconnect my airpods so the speaker plays and the mic picks it up."
],
"score": [
14,
6,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gf9ef5
|
why are printers so needlessly confusing and cryptic?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpsmlow",
"fps74ag",
"fpsh918"
],
"text": [
"I strongly suggest you do a cost analysis. It actually turns out MOST people would save more money by using a print service than they would owning their own printer. It's not financially worth it even for the occasional \"quick print\". Bear in mind manufacturers design printers to use as much ink as possible, to punish you for using off brand ink (as a form of mental conditioning), to prevent you from refilling or reusing cartridges, they won't even use their entire cartridges, which have a limited shelf life (cartridges didn't always \"dry up\" or get clogged until they realized shitty cartridges meant people would buy more), and all modern printers have planned obsolescence - where the damn thing will just stop working to force you to buy a new one. Planned obsolescence is mostly designed to force you to buy a new printer so that you'll buy a device with more modern money wasting and behavior controlling DRM and technologies they've invented. The whole industry and their product strategies are utterly toxic. Even at the commercial level, office and industry printers break, All. The. Time. Because the manufacturers make big bucks selling service certifications to 3rd party service companies. They've invented their own market! So that printer at the FexEx Store that cost $300k is built to break. And everyone knows it. The cost of ownership over the lifetime of the product is very likely more expensive than the cost of a print service, which you can order online and pick up at your convenience, or do it in the store, or even through your library. So your whole experience is bad because it makes them money to be bad at every juncture. If they were losing money because of bad products or customer service they'd fix it in an instant. I have a printer from the 80s that works to this day, gives me absolutely zero fuss, I can refill the ink myself, and there's nothing I want to print at home that it can't. Things were literally better decades before when the market was much smaller and far more demanding. But now everything is so disposable, consumers have proven they care about price points more than quality or even functionality, and their business model works - literally scam you, and you'll keep coming back.",
"Consumer tech. You're buying what is actually a quite complex device, full of quite complicated technology, and trying to get it as cheap as possible. Manufacturers will of course then cut corners where they can, and support is an obvious one. So is software, which is often pushed out of the door as soon as possible. The other side of the equation is that they got your money, so the less time they spend dealing with your issues, the better their profits will be. If you really want, you can certainly have quick support even at 3 AM on Christmas, you've just got to have a support contract and pay through the nose for it, so such things are reserved to companies where something not working can mean a lot of lost money.",
"In many ways, a modern printer is as complex as a personal computer, and in some ways it is much more complicated. Printers do a lot of sophisticated processing work and have a surprising amount of “horsepower”, with all the complexity that goes with that. In addition, modern printers often have complex features like wi-fi, bluetooth, and other network interfaces, and even email. Your personal computer has all of these features. But the operating system is the product of countless millions of dollars of research and development, not to mention decades of work, not to mention application software like your web browser. A modern computer operating system is a *wonder* of engineering. But the basic “home” edition of Windows 10 costs more than a hundred dollars. Sure, Microsoft is making a healthy profit on that, but on the other hand the costs of development are spread across hundreds of millions of users. It simply isn't economically practical for a printer manufacturer to produce an interface of similar quality. Even ignoring the hardware constraints — a tiny, cheap screen, few inputs, limited processing power — it just doesn't make sense for the manufacturer to spend even a fraction of the time and money on the printer interface as goes into a computer operating system. It would noticeably increase the cost of the printer, and consumers are sensitive to that — people buy printers based on features and print quality, and even if a printer's interface is genuinely better than the competition it's hard to sell customers on this."
],
"score": [
18,
10,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gfcntk
|
How do movies and live videos switch between camera angles while maintaining the audio perfectly?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpsqiaf",
"fpsw33y"
],
"text": [
"I'm not sure I understand your question. The audio is entirely separate from from the cameras, it's not recorded at/by the cameras. So changing cameras won't affect it.",
"* For live videos it's easy: * Everything is captured by a mic. * The mic is totally separate from the camera so switching between cameras has no effect on it. * For movies things are slightly more complicated. * Again everything is captured by a mic that is totally separate from the camera. * However, since multiple takes of the video and of the audio can be used and cut together, there needs to be a way to sync the captured audio with the captured video. * This used to be done with a *clapper board*. * It's that super cliche thing that a worker slaps in front of the camera when they yell something like \"Scene 9 take 4\". * The clapper makes a loud sound that is easy to find in the recording, and also makes a very sharp moment that is easy to see on the video. * This means the editor can easily line up the recording of the audio with the recording of the video. * Now-a-days both the camera and the audio recorder have an input for something called \"time-code\". * A separate machine generates this code and is wired into the camera and the audio recorder. * When the camera and audio recorder are rolling, they also record the time-code signal. * Later on, during editing, the software can access the time-code portion of the recording and precise line up the audio with the video. * The other thing is clever editing. * If you notice when the camera cuts, it's almost never to another angle of the same person talking, it's always to something else, or someone else listening. * Sound editors also use a trick called \"room tone\". * They make long recordings of the sound the the room the actors are in even when it's empty. They use this \"room tone\" as a backdrop for the actual dialog. That way when they cut from one take to another, you don't hear hard transitions because the room tone covers that up. * In movies this is mostly done by creating room tone artificially from a huge library of sound effects."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gffob9
|
How does a RAID 5 file storage system use less space than mirroring?
|
If I have four disks and I'm using RAID 1 (mirroring), I can only store two disks worth of data, because of the other two backup disks. This makes intuitive sense. If I have four disks RAID 5, I can store three disks worth of data, and yet still be able to restore all lost data if one of the drives fails. How can the system restore any failed drive without having enough space to store all data in duplicate?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fptpwj8",
"fpt9xra"
],
"text": [
"> How can the system restore any failed drive without having enough space to store all data in duplicate? Short answer: it plays Sudoku. Imagine having a table with 4 columns containing numbers and an arbitrary number of rows, and the sum of each row is constant. At that point you can erase any one column (but no more!) and still be able to recreate it. Do note that to recreate the missing column you need *all other three*. You lose one more, you're fucked. Well, RAID5 is the same thing, sort of. Your data is spread onto 3 drives and the 4th keeps so-called \"parity information\" computed according to a particular rule such that, in the event of the death of any one drive, the system will be able to use the data from the other three to rebuild the RAID. Suppose your data is made up of decimals and looks like: 4, 2, 3, 1, 8, 0, 3, 3, 0, 1, 2, 5 We can subdivide it into 3 columns (drives) like this: +---+---+---+ | 4 | 2 | 3 | +---+---+---+ | 1 | 8 | 0 | +---+---+---+ | 3 | 3 | 0 | +---+---+---+ | 1 | 2 | 5 | +---+---+---+ and compute a 4th column such that the sum of each row is always 10: +---+---+---+---+ | 4 | 2 | 3 | 1 | +---+---+---+---+ | 1 | 8 | 0 | 1 | +---+---+---+---+ | 3 | 3 | 0 | 3 | +---+---+---+---+ | 1 | 2 | 5 | 2 | +---+---+---+---+ Now your second drive dies because you bought that WD green crap: +---+---+---+---+ | 4 | ? | 3 | 1 | +---+---+---+---+ | 1 | ? | 0 | 1 | +---+---+---+---+ | 3 | ? | 0 | 3 | +---+---+---+---+ | 1 | ? | 5 | 2 | +---+---+---+---+ Rebuilding it, knowing that each row must add up to 10, is left as an exercise. The missing element in the first row must be `10 - 4 - 3 - 1 = 2`, and so on.",
"RAID 5 + 6 use a technology called Parity to add redundancy. Parity uses a mathematical function called XOR (exclusive OR). XOR works as follows, for any 2 binary inputs XOR returns a 1 if the two inputs are different, or 0 if the inputs are the same. 0 XOR 0 = 0 1 XOR 0 = 1 0 XOR 1 = 1 1 XOR 1 = 0 When you write bits on an RAID 5 array, you perform a XOR function against all the bits and store the result on the final drive. For example with 4 disks 1, 0, 1 (disk 1, disk 2, disk 3) with disk 4 with the parity data. 1 XOR 0 XOR 1 = 0 ( 1 XOR 0 = 1, 1 XOR 1 = 0) If you lose any disk in the array you can use the parity to recover the data 1 0 ? Parity = 0 1 XOR 0 = 1 since Parity is 0 the missing but must be the same so it's 1. RAID 4 uses a dedicated parity drive (which is very rarely used these days) RAID 5 stores the parity information spread evenly across all of the disks on a block-by-block level, but you ultimately lose 1 disks worth of data for the parity info. RAID 6 is double parity, meaning that it writes parity data twice. This has the upset that you can lose 2 disks and still recover."
],
"score": [
8,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gfgm3c
|
people are saying Tik Tok is a Chinese data mining operation
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpth8te",
"fptgcjy",
"fpticdp"
],
"text": [
"Can't speak to the consequences, only the rumors. Note, what follows is conjecture and common sense. Because access to information about the inner workings of the Chinese government is pretty much impossible one has to extrapolate from what has been seen/experienced and reported previously. China is a monolithic dictatorship with a semblance of representation in a governing body. In reality that government body serves at the will of the Chinese Communist Party and it's leadership. All business in the country must be authorized by the government. No authorization, no business. All data services must be routed through a network controlled and monitored by the Party. No proper routing, no access to the world. This is why pretty much the only way Chinese internet users can get access to non-censored material is through a VPN. All software that uses internet connectivity must have back doors built in allowing real time access to the monitoring agencies of the Party. So, Tiktok is a Chinese app. Its design has to comply with Chinese law. That law requires it to be approved by the CCP, and to have back door access. Many Chinese advances in technology over the last 40 years have come from spying and stealing secrets. In the Internet age it is much easier for people to discuss things that they maybe should not in easily spyable forums. You can decide from there whether someone can, or even would, try to mine data from it.",
"Everything you say and who you say it to is known by Chinese authorities. They can use this information to investigate your friends, and they don't have a history of being nice to people who have said things critical of them. So, that friend of yours that likes posts by protestors in Hong Kong can be tracked using your communication with him. Probably nothing bad will happen to your friends, but that's no thanks to you.",
"TikTok is owned by a Chinese company called ByteDance. ByteDance is officially a private company, but like every other \"private company\" in China it is effectively controlled by the Chinese government. Tiktok loses vast amounts of money on its non-Chinese operations and does not appear to *ever* have plans to monetize the operations. The fact that its losing money isn't super unique among tech companies - Reddit loses money, for example. But tech companies that lose money still try to monetize their content and have a long term vision under which they do eventually start making money. Tiktok doesn't. The questions is then why is the Chinese Government willing to indefinitely absorb loses that would be catastrophic for any other company? The only real answer to that is because they view the app as having strategic value far in excess of its monetary loses. Part of that value can be in the app's ability to manipulate you - Tiktok can very easily promote videos sympathetic to China or Chinese interests while diminishing the likelihood that videos which go against Chinese interests are showed in your feed. Another part of that value is in its ability to collect data. For example, the Chinese Government can collect location data on US service members who have Tiktok on their phone to figure out troop movements. It can use location data to identify videos that were taken in non-public areas - say a janitor at Apple takes a video while at work. Tiktok knows the video is coming from a high security building at Apple's HQ and sends that video to a Chinese Government analyst group who pour over it to see if they can spot a schematic or other secret document out in the open. Even if the video is public, without the location data that Tiktok is able to get through its app it would never actually be able to identify that particular video as being important to begin with. IE, say the video was uploaded to Youtube. Sure China could look at the video *if they knew it existed* - but they have no way of knowing that it existed without that location data that only comes from the app. Then you also have another concern with such harvested videos - the cameras on high end phones can record at resolutions way in excess of 4k. They don't because no one has the bandwidth to upload that - but they can. So even though our janitor may be uploading this video which contains sensitive documents in the background, at 720p on youtube, you can't actually read those documents. Its entirely possible for Tiktok to use location data to identify people in high value areas and then have their phones secretly record the videos in ultra HD and just upload them over a long period of time, greatly increasing the risk of data exposure. But maybe you're not a US service member or someone who works in a high security environment. Tiktok has your name, address, phone number, and a bunch of other identifiable information about you. From that the Chinese Government is almost certainly creating a profile with every video you record through the app. This way, if you become someone important later on the Chinese can go through all of that to see if there is anything embarrassing that they can use to blackmail or otherwise harm you. Again, just because this stuff is public doesn't mean its possible for them to find - if you're uploading it to youtube the Chinese Government doesn't have all of that personal data tied to the video so there's really no way for them to find it. On top of that, the youtube video doesn't give them your location data. Its possible for the Chinese Government to use your location data to find out embarrassing stuff about you all on its own - say you go to a gay bar or they see that your location data shows that you're sitting in the same car as someone else with Tiktok that the Chinese Government knows is a prostitute. The Chinese Government knows that *forever* and will use it against you if it ever has the opportunity to do so."
],
"score": [
6,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gflh7y
|
how does electricity actually power things
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpucckv"
],
"text": [
"One common metaphor that's used is that a wire is like a hose, and a full battery is kind of like a full tank of water on the top of your house. A battery has potential energy in the form of a charge difference (one pole has more electrons than the other, and they want to go to the other pole), just like a full tank of water has potential energy from gravity. When the circuit is complete, the electrons can flow through, providing energy, like the water in the hose. To get a little more technical, a lot of applications involve making use of the charge differences, specifically. The moving electrons can induce a charge in an object, creating a temporary magnet (called an electromagnet) that can then cause motion. This is how electric motors work, as well as electric bells. Obviously, it gets more complicated than all of this, but we're shooting for simple, and this is my best shot."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gfn41p
|
What happens if you don't turn airplane mode on?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpunfdo"
],
"text": [
"Cellphones get their connectivity through their access to cell phone towers. Like all forms of technology, connecting requires power. When you’re relatively close to a cellphone tower, your device uses relatively less power, than being far away from a cell phone tower. So if you’re on an airplane, you’re going to be miles and miles away from the nearest cell phone tower, and if your device is trying to connect to them, it is going to consume more power. This can interfere with the radio transmission from the pilot to air traffic controllers. Now, a few people not turning airplane mode on will not cause much of a disturbance to the pilots, because aircrafts are designed to block interference, to a certain degree. However, I imagine if every single device on the plane is attempting to connect to a cellphone tower, there will be noticeable and significant interference to the pilots. It will not cause the plane to crash or make the aircraft malfunction, but you obviously wouldn’t want to distract your pilot; the same way you wouldn’t want to distract your driver."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gfreuy
|
why the handling of OSs is easier on a PC than on a phone.
|
ELI5 why is booting, installing, replacing and testing operating systems on a PC or laptop so much easier and safer than on a smartphone? Why is bricking so prone to phones while I have never really heard of laptops or desktops becoming useless due to any incorrect handling of the boot process?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpv85yk",
"fpva9lp"
],
"text": [
"Long story short: when you replace the software in the phone, you ALSO replace the software that helps with uploading and starting up new software. The software that does that in a computer, the BIOS, is also extremely delicate when you have to replace it. But you barely ever have to, which is why it's not talked about as much.",
"A computer isn’t just made up of an operating system. It also has a BIOS - which is basically the bit of software that performs the initial checks of the computer itself before handing off to the main OS. On a PC, the BIOS has pretty much no say in updates or anything. On a phone, the BIOS is called the bootloader. It *is* responsible for updates, and are normally tied much deeper into the operating system. To add to that, the bootloader is not made to be used by the end user, more so the manufacturers or repair people with dedicated software. For that reason, because you need dedicated software to even read this bootloader - and in some cases you even need dedicated hardware - it’s a lot easier to brick because your very unlikely to be able to re-reprogram a chip if something does go wrong and a chip goes corrupt."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gfurl7
|
Why chipset based graphics discontinued?
|
In olden days before the core series from Intel, motherboards used to have small graphics chipset on it. Rather than being integrated on the cpu. Why was this discontinued? Current gen mainstream AMD cpus do not have processor based graphics like the Intel ones do. (the G series parts come very late and technically are low end stuff.) sometimes you do not need a discreet gpu. So why was chipset graphics discontinued, it could have been used to decrease the cpu complexity on Intel side. While Amd would not need to have to launch apus. Hence saving development time.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpvuexg",
"fpvrpdh",
"fpvu8u2"
],
"text": [
"There was a move to consolidate features from various chips on the board into the CPU Originally motherboards hosted the CPU, Northbridge(Memory Access, high speed ports, and iGPU), and a Southbridge(Slow access ports like PCI and USB) As time went on and we consolidated towards PCI-e the Southbridge lost its purpose and was dropped. Secondary port types are covered by a PCI-e to whatever converter chip. Then we moved memory controllers into the CPU and gave them support for PCI-e internally. The Northbridge (which used to host the iGPU as well) lost most of its purpose so the remaining features were absorbed by the CPU. Starting in 2011 the mainstream AMD and Intel CPUs had absorbed all of the features of the Northbridge into the CPU so there wasn't a high speed connected chip left to house the iGPU, it had to be built into the CPU if it was to exist at all. This gave us a lot fewer compatibility issues, and allows for much smaller boards where the only thing that needs cooling is the CPU (the northbridge used to have a heatsink and sometimes a fan). This means that you can build a micro ITX PC and put it in a tiny case which wouldn't be possible if you had to fit a CPU, northbridge, southbridge, and RAM onto the board.",
"Those chips cost money and take up valuable mobo space. While the integrated graphics costs money, it costs less money than those chips cost. Oh yes, and making it harder for AMD to make money is something Intel is very, very keen to do. Intel offers mobo makers a way to save money, and it causes AMD to spend lots of staff-years designing new graphics circuits instead of having mobo makers buy chips. That's what Intel calls a WIN-WIN.",
"Both Intel and AMD, over the years, have moved many functions that would previously have been handled by part of a motherboard chipset to being part of the CPU die/package. This includes just about everything that would have also been bundled with a chipset GPU on older motherboards. From a technical perspective, there could be a huge bandwidth penalty for placing a GPU directly into the motherboard, since it may have to use the PCI Express lanes coming from the chipset unless it were to cannibalize the lanes coming directly from the CPU (taking away lanes from a discrete graphics card or pci express solid state drives). Also keep in mind that integrated GPUs don't have their own RAM: they must share RAM with the CPU. If placed on a chipset PCI-e lane, the graphics card would be bandwidth starved to hell just trying to access the system RAM. There's just no incentive to create a solution like this. Basically, in terms of both cost and performance, it makes sense to place a basic GPU on the same die/package as the CPU than anywhere else."
],
"score": [
9,
6,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gfvkqe
|
In what way does crypto "money" differ conceptually from the virtual money in one's bank account?
|
The virtual money in this case (an online statement) doesn't actually exist, it's just a value system used by the bank to be translated into hard cash if ever you have to make a withdrawal. But that virtual currency isn't a thing in reality, even if on the backend it might have its own funky way of working in the financial system. So how does that compare to crypto? Like with any currency, value is determined by 1) how useful it is to us and 2) what we say it's consequently worth, so what's the conceptual difference between, say for example, 20 chainlink (for example) "dollars" and 20 virtual dollars in my bank that represent cash? Are they *actually* different things, and if so, how?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpwcl2t"
],
"text": [
"Money is broken down into two types, fiat and commodity. Commodity money has some sort of commonly applied purpose, and that common purpose makes the money inherently useful and valuable. The idiom \"you aren't worth your salt\" comes from the Roman army. Rome had so many soldiers in so many different areas with so many different local currencies, they wanted to pay their soldiers with one thing that was universally valuable to simplify their payroll, so they chose salt. Salt is lightweight, easy to carry, doesn't spoil, can be easily divided into specific amounts, and everyone everywhere recognizes it as valuable. The trouble with commodity money is that state has no way to control how valuable it is. Imagine you're a Roman soldier who's been scrimping and saving his salt so he can send a bunch of \"money\" back home to his family. Right before he does so, someone invents a really cheap way to recover salt from seawater. There's suddenly many, many times more salt floating around and it becomes much cheaper. This Roman soldier's savings are now worth significantly less and he's understandably upset. If the entire Roman economy worked with salt as their form of currency, the whole economy would be thrown wildly off balance. Fiat money has no inherent value. The only value it has is the faith that people have in it. I have no problem selling my car, an inherently valuable item, in return for a bunch of paper pieces with pretty pictures on it because I have faith that when I want to purchase something from someone else, they'll be willing to accept US dollars in exchange. While fiat money can be a little scary as you're essentially putting your trust into a bunch of IOU coupons, the value of fiat money can be controlled by the state as the state can make or destroy fiat currency at will, which allows the state to stabilize prices and keep the economy going more smoothly. Crypto and dollars are both fiat currencies. The only value they have is the faith people have in being able to exchange their fiat for actually useful goods in the future. The meaningful difference is that one is state-controlled, and thus more stable, while the other is lacks central control and thus is inherently more volatile."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
gfwrji
|
how does the autofocus work in a DSLR camera?
|
I know it's something related to the camera changing the focal length until it obtains the sharpest image but does it know which one is the sharpest image?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpw5cfa",
"fpx61a6"
],
"text": [
"It evaluates the sharpness by edge detection. It finds the line that divides the highest brightness and color change, then changes the focus to create the sharpest, most abrupt change across the line. They get more sophisticated by testing several areas and more recently, prioritizing face detection.",
"> I know it's something related to the camera changing the focal length until it obtains the sharpest image Wrong; that’s the cheap way. It’s slow too because you don’t know whether to try focusing nearer or farther and the camera often has to try both ways and then overshoot before settling on a sharp focus. Working out how sharp an image is is simple: sharper images have a bigger average difference between adjacent pixels. DSLRs use phase-based auto-focus. Effectively they can compare the image seen by the right-hand side of the lens with that seen by the left. This used to require extra image sensors but now a version of the system can be built in to the main image sensor. It has the advantage of being able to tell which way you’re out of focus and by how far, so the lens can quickly adjust correctly. They can even work out if the subject is moving nearer or farther, like in sports photography, and continuously predict the best focus."
],
"score": [
14,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gfycfe
|
why are soap operas so obviously soap operas?
|
to clarify, what im asking is why do you always know? i cant figure it out. even with no volume, you can tell. and if you actually watch for a minute, the acting is really not bad, objectively speaking. many actors started on soaps. is it a very particular camera equipment, or shooting technique?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpwg03a",
"fpwe1yi",
"fpwesja"
],
"text": [
"Soap operas are produced very quickly and very cheaply; this has been part of their process for decades and has given rise to a lot of tricks that give them their distinctive look. The two biggest ones are filming technique and lighting. Because they were filmed so quickly and on such a tight budget, classic soap operas weren't actually put on film, but were instead recorded straight to videotape. This meant that instead of the 24 frames per second that we associate with film, they were getting 60, giving the video a slightly different vibe. We're still really used to 24 fps - even now that almost everything is filmed digitally, they're still mostly putting movies out at 24 fps because it \"looks right\" to a film audience. Some directors have tried to buck that trend - I remember that Peter Jackson filmed \"The Hobbit\" in 48 fps - only to be met with complaints that the movie looked cheap, because on some level we associate that higher-frame-rate movement to cheaper television. The other big one is lighting - since soap operas try to film their coverage as fast as possible so that they can meet their production schedule, they don't have time to light each and every shot, so they instead go with a fairly diffuse lighting across the whole set so that actors can move around and not worry about losing their light. This, combined with mostly smaller indoor sets, makes the actors seriously backlit and gives them that \"soap opera feel.\" Other mediums, like say multi-camera sitcoms, will light the whole set, but since they're using larger sets, brighter lighting, and film (or digital) cameras, they aren't quite as pronounced. Modern soaps actually try for that look because it's what people expect.",
"As I recall, there is a difference in the frame rate that soap operas typically use than most other television. It gives them a distinctive look that, as you said, you can't directly tell but you know what it is when you see it.",
"Soap operas use cheaper equipment that have a different resulting quality than higher budget productions. For instance, they'll use 60FPS camcorders instead of the professional 24FPS film cameras that a high budget movie would use. This results in a lot of smaller movement that you end up seeing that is \"lost\" when filmed at 24FPS."
],
"score": [
16,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gg0xk7
|
How can you dial the emergency numbers without a sim card? How does it work actually without network too ?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpwtre2"
],
"text": [
"Well, it doesn't work without network. Its a regulatory requirement that if the phone can see or be seen by any cell network (of the same technology, GSM, 4G whatever) it HAS to always be able to make an emergency call. All cell phones have the potential to contact any network its compatible with - however the network simply ignores it unless it has a SIM card that proves the holder of that SIM has paid to use the network. I think emergency mode on phones also kills background apps and anything else to prioritize signal strength and battery life too, but I've been out of the field for a while, so not sure about that. I'd be interested to know though, if a SIMless phone was within coverage range of multiple compatible networks what the criteria for which it would use for an emergency call would be. Probably best signal strength. Would be curious to know what the handover between networks would be in that case. So there's a LPT for you. In your emergency go-bag or car emergency kit, keep your old phone w/o a SIM and a battery pack thing, you'll always be able to make an emergency call."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gg3z0p
|
Shouldn't we be putting HEPA filters on every air conditioner and heater? Don't HEPA filters take viruses out of the air?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpxcmi9",
"fpxe0dn"
],
"text": [
"The problem is not the virus lingering in the air, it’s people sneezing and people breathing in the aerosol, or people sneezing, the snot going onto surfaces and people touching the surface and then their mouths",
"HEPA filters take damn near *everything* out of the air. [This]( URL_0 ) is what a typical air filter out of a home AC unit looks like after I'm guessing around 3 months, which is the recommended time to replace them. That particular filter is pretty dirty so it might be closer to 6 months, it's hard to tell exactly. When I worked in a small aquarium store we had to change all three filters *every* month and they looked worse than the one in that picture. After two months they would get so clogged that it caused the evaporator coils to freeze. That's a filter that only catches pet hair, clumps of dust, fuzzies, and *maybe* pollen if you spend $20 or $40 for the good ones designed to catch it. Pollen is [orders of magnitude larger]( URL_1 ) than viruses. So not only is the HEPA filter catching the viruses, it's catching every single thing larger than the virus that gets caught up in the filter. If all of that stuff *larger* than pollen will clog a filter up that quickly in a commercial setting, you can imagine how much faster they would clog when they have to catch all the particles down to the size of a virus. That would be an outrageous cost, since HEPA filters are so much more expensive, and they would have to be replaced so much more often. We had three AC units for a *small* store. A large store will have both more units and larger units that require specialized (ie: more expensive) filters. There isn't enough benefit to justify that cost. Not all of the air gets circulated all the time, so viruses will still linger. It won't remove viruses from surfaces. It won't get rid of the viruses immediately after a sneeze. It really won't accomplish much."
],
"score": [
19,
9
],
"text_urls": [
[],
[
"https://thecomfortauthority.com/wp-content/uploads/2014/02/Dirty-Filter.jpg",
"https://slideplayer.com/slide/13051742/79/images/6/Sizes+of+biological+particles.jpg"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
gg4nn7
|
Why metallic notebooks vibrate when you touch them while charging?
|
Don't know if its really a vibration, but when I move my finger/hand over the metallic surface i feel like a vibration/buzzing, while it disappears when i find an sticker or label.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpximrf"
],
"text": [
"The laptop is not grounded properly and is coupling some mains electricity through you to the floor. If you unplug it you won't notice it anymore. Its harmless though at such a low current."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
gg4ssr
|
How does collision detection worin in video games
|
How do you get data like coordinates and convert them to a true/false of intersecting something else?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpxlehp",
"fpxl8lw"
],
"text": [
"First you have to define a boundary which interaction with counts as a collision. This is usually not the model itself since the model is very complex, made up of lots of small, moving faces. The collision box is often very simplistic, sometimes just that: a box. Determining if two boxes overlap (collision) is actually fairly easy. Each box only has 8 vertices which will have well defined coordinates. If all of the x-coordinates OR all of the y-coordinates OR all of the Z-coordinates of one box are greater (or less) than all of the corresponding coordinates of the other box, then they aren't intersecting. Otherwise, it is.",
"I’m only a tinker with making games so anyone else feel to correct me. The easiest way to think of it is for 2D games. As fair as I’m aware the most basic way is very much like you said. The programming engine basically calculates everything on a grid. If you have a square on that grid it “knows” the coordinates of one corner of a square and also the width and height. From this it “knows” all the positions which the square is occupying. Then when your character comes along it will have what is called a collision mask. This can be as simple as a square in 2D games but can also be made to fit the sprite or model in more advanced situations. Usually movement code would wait for you to ask it to move the character, then it would check to see if there was room to move by checking all the players collision mask will take up after it moves. If it finds points that are inside your square it will then not move. As I said I don’t know much but I believe there are more advanced alternatives. Most game engines (Unity,Unreal etc) handle this for the coders. Hope that made sense"
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gg7p2s
|
Why isn't everything in compressed/smaller file?
|
From my understanding, ZIP files are much smaller than regular files and are compressed. There are probably other forms of file compression too. Why aren't these a standard if they save space/are smaller?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpyaa2b",
"fpy2flm",
"fpy3l0o",
"fpy2ztv"
],
"text": [
"Compression is extremely common in application file formats. For example, Microsoft .docx and .xlsx files are actually ZIP archives. Image formats like .jpeg, .png, .gif, are all compressed; [.jpeg uses lossy compression]( URL_1 ) while .png and .gif are lossless (although .gif can lose some color information), but they all use compression schemes appropriate to images. For multimedia, .mp3 and .mp4 are likewise specialized compression schemes appropriate to audio and video data. Video codecs like [H.264]( URL_7 ) are basically highly specialized compression schemes. In general, these specialized, domain-specific compression algorithms do much better than a generic algorithm like [DEFLATE]( URL_4 ) (the default compression algorithm for .zip archives.) Web servers and browsers also have the capability to compress files in transit (negotiated via the [Accept-Encoding]( URL_3 ) HTTP header.) For example, the very popular [mod\\_deflate]( URL_0 ) for Apache will compress plain text files such as .html files on the fly to reduce the amount of data sent over the wire. Video games are an interesting case. In an typical large 3D game, textures will take up about 2/3 of the disk space. Textures are routinely compressed; for example, the very popular Unity framework does this when building projects. For other game assets, sometimes everything is placed in a compressed archive, sometimes it is better to leave it uncompressed. For example, [this guide for Unreal Engine]( URL_2 ) gives different advice for PS4, the Switch, etc. Databases are another interesting case. While some database can optionally compress tables, this isn't always a good idea. You see, once you've compressed a file, you can basically only read it from start to finish, in order; you can't really jump around and you certainly can't make edits to pieces of it. It also makes it harder to keep indexes in sync, which is a big part of what databases are supposed to do. So, typically only tables which are going to be used for analytic/[OLAP]( URL_6 ) use cases (read-only, full table scans, hash joins) benefit from compression, while tables that are more transactional/[OLTP]( URL_5 ) (lots of inserts, edits, single-record lookups, and nested loop joins) usually should be left uncompressed. Pretty much the only files that are not routinely compressed are plain text files used by software developers: files such as source code or log files. Programmers routinely view and edit these files directly as well as use various utilities on them, so it is convenient to have them in a raw, uncompressed format at disk. Such files are generally tiny compared to multimedia files so this is not a big deal. Even then, these files will be compressed when it is appropriate to do so; for example, Apache will compress log files that are more than a few days old by default, and programmers often move their code around using programs like git which use compression to quickly move files about. So I think the answer is, they do, it's all around you, and it works so seamlessly you hardly notice it.",
"Compression required a lot of work to both store and read the compressed file. There are many cases where the file size savings aren't worth a performance penalty",
"Because writing the file and reading the file takes longer. You have to run cpu cycles to do the compression and decompression",
".zip has been used as a standard because - it's open source and free to use - it's versatile and works with a lot of different file formats - is supported on multiple platforms as well as commercially - is more efficient when the computer is doing multiple things at once That's about as simple I could put it without getting too technical or going into the history of the compression race, which I honestly know little about."
],
"score": [
22,
11,
3,
3
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Mod_deflate",
"https://en.wikipedia.org/wiki/JPEG#Compression_ratio_and_artifacts",
"https://docs.unrealengine.com/en-US/Engine/Basics/Projects/Packaging/index.html#compressingyour.pakfile",
"https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Encoding",
"https://en.wikipedia.org/wiki/DEFLATE",
"https://en.wikipedia.org/wiki/Online_transaction_processing",
"https://en.wikipedia.org/wiki/Online_analytical_processing",
"https://en.wikipedia.org/wiki/Advanced_Video_Coding"
],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gg8vlk
|
Why do ads show up for things I’ve only talked about and not searched for online?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpyc9hz",
"fpyj2p4",
"fpyis7i",
"fpyn5r4",
"fpydlqf",
"fpydxe1",
"fpztv7g",
"fpzj44e",
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"text": [
"Pattern analysis. You search for other things and a computer with alot of data figures out that the type of person who searches for these 5 things but not those 8 probably is interested in this new thing. It can be scarily accurate depending on how much data the computer has (a metric crapton in terms of Google/Amazon)",
"This will not be a popular answer, but it's usually just down to confirmation bias... Americans for example, are exposed to up to 10,000 ads per day... The chances are at least one or two will be related to something you've spoken about or otherwise experienced recently and because of that connection, those are the ones you'll be more likely remember.",
"Oh? You mean like how Target can predict your pregnancy due date? I'm just going to leave [this]( URL_0 ) here...",
"It's a combination of good ad-targeting based off the information about you that is available, along with confirmation bias. There is a lot of information about most people available to advertisers. Even a *lack* of information is a hint to them (wouldn't be surprised to see more VPN ads for people using incognito mode). Based on this info, along with cross referencing the with others who have similar info, very good guesses can be made. On top of this, we see ads all the time. You are likely to just filter out an ad that isn't relevant or interesting to you, but there's a much greater chance of you paying attention to and remembering it if you've just learned about the subject or had a conversation about it. We don't remember the thousands of times this coincidence *doesn't* happen. Many people think their devices are always listening/recording/transmitting them. There are several reasons this isn't the case. Among these are the expense of doing so, battery requirements for mobile devices, data transmission/analysis/storage costs, legality, very knowledgeable people looking and testing for this practice, and the PR disaster that would result if discovered. I'm not saying any one of these things makes the practice impossible, but together they are a huge disincentive. I've seen plenty of tests showing negative results, but I have yet to see any serious evidence of devices constantly listening (ignoring of course where the practice is explicitly stated, or fringe cases involving malware or hardware hacking).",
"It's really bizarre. Many times it was something completely random said in conversation that would not fit with a pattern. Like if you said a thing which also happens to be a brand name for some random product that an ad is now displayed for in fb.",
"Because your data has been collected and you are predictable like most other people. Or tin foil hat your phone is sending every fart to google for analysis.",
"I have to add an answer here that most people don't think of. Of course data analysis and confirmation bias are part of it, but there is another piece of the puzzle. When this happens ask yourself why are you talking about something that is related to the product being advertised in the first place? Is it possible you are having that conversation because of something you read about on social media? How many conversations do you tend to have that aren't fed in some way by your consumption of social media. You didn't see the ad because you were talking about the thing. You were talking about the thing because social media told you to talk about the thing. Then they show you the ad after you are already primed.",
"You either searched for them and forgot, mentioned then in WhatsApp or Messenger, or it's confirmation bias. Example that happened to me the other day. I suspected Reddit was giving my posts to advertisers because I saw an ad for a band that I mentioned in a comment. I'd actually forgotten all about this band, so it was suspect that I saw an ad for them in the hours after I posted. But then I remembered I *did* Google the band to find out if they were a one piece or a group. WhatsApp and Messenger also use your messages for ads. Lastly, there's an element of confirmation bias. Confirmation bias is where you are more likely to notice something that confirms one of your beliefs, or that's in your mind. If I were to say to you 'blue cars are everywhere lately' you'll start noticing blue cars everywhere, even though the number of blue cars hasn't changed. You scroll past hundreds of ads every day. For every 30 that your ignored, you notice the one that's been on your mind lately. You might have scrolled past that same ad previously without paying it any attention, but now you're thinking about it it's there and it feels weird.",
"If you are into podcasts there is an episode on this kind of thing on Reply All. Episode 109. Pretty interesting/creepy.",
"Marketing companies hooving up all of the data that they can. They use any piece of information that will increase your chance of buying something. Youll see it referred too as data driven marketing. How do they get this data? By trying to record your every action. Whether it be a app that is recording everything in the background and analyzing it, how you interact with a webpage, who your friends are, Location data, etc. Even your smart TV and Fridges are recording what you do. If you go and buy a movie ticket, there is a good chance that someone will buy that data and analyze what movie did you buy, did you upgrade to a greater experience, what did you buy at the concessions, etc. Though its worth keeping in mind that this process is almost entirely automated and a computer is just trying to sort through it to figure out what your most likely to buy Even your ISP will spy on you. Not just with supercookies but your DNS records, http traffic, etc. [ URL_1 ]( URL_1 ) [ URL_2 ]( URL_0 ) (You can stop this one by using a third party DNS server)"
],
"score": [
178,
55,
39,
23,
12,
11,
9,
5,
4,
3
],
"text_urls": [
[],
[],
[
"https://techland.time.com/2012/02/17/how-target-knew-a-high-school-girl-was-pregnant-before-her-parents/"
],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/DNS_hijacking#Manipulation_by_ISPs",
"https://www.theverge.com/2016/3/7/11173010/verizon-supercookie-fine-1-3-million-fcc",
"https://en.wikipedia.org/wiki/DNS\\_hijacking#Manipulation\\_by\\_ISPs"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
gg9ove
|
Are GPS systems that track speed in vehicles (MPH) inaccurate if a person is going up a hill?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpygyzs",
"fpyifsc"
],
"text": [
"No road has that kind of slope bro. Max vould be about 15°. But I think it takes the elevation into account. After all the satellites are not right above you",
"Short answer - yes. Most GPS systems do not account for your angle and will only tell you your speed relative to, basically, level ground. It's worse than that, though. The rate that most automotive GPS systems update your position is very slow, (often as seldom as once per second) so if you're on a long curve, it reports a lower speed as well. Thankfully, the difference is usually less than 1% so it won't make much difference if you're looking at units as large as a Mile per hour or even a Kilometer per hour (though KPH is more noticable). Depending on when you get your last update and when you pass under a bridge, it can be *very* noticable, though. Losing satellite reception on some units can make them \"rubber band\" your position when it does finally sort out where you are. My GPS currently says my max recorded speed is 343 mph because of this."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggc013
|
How did Flour become a Thing?
|
I see modern agricultural grasses as worth harvesting because they are humongous and planted next to each other in fields. And we have the whole grinding them into flour thing. Did cavemen go around stripping the seeds off of what I imagine as similar to what modern-day prairie grass grows? What did they do if they had little nutritional value without grinding them (how did they learn to do that)? Is there an equivalent in chimps or some other primate? I guess I can see it as a snack found randomly in the wild, but slowly breeding it to become larger is hard for me to see coming naturally. Basically, I don't get how grains/wheat/flour became a thing. Can someone tell me?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fpzaguh"
],
"text": [
"There are actually groups of apes and primates which does use stone tools to smash open different kinds of seeds and roots to get to its nutritious insides, thereby making flour. However even though flour was used throughout all human history most grains was boiled and not crushed. Even today it is popular to eat cereal grains instead of baking it into bread. Domestication and breeding of plants probably came quite naturally as well. People would settle where there were plenty of food to harvest. And they would essentially take ownership of patches of good food sources and care for them. And it is not hard to see that seeds creates plants as this happens quite often on accident."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
gge2pm
|
What is fracking? Why is it so dangerous?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq016p4",
"fq0009e",
"fpzy5x7"
],
"text": [
"Drilling for oil and natural gas is mostly vertical. You poke a hole straight down into an oil or gas pocket and bring it to the surface. Because the stuff at the bottom is under pressure from all the stuff above it, it flows upward. You can think of fracking as drilling horizontally. Instead of straight line down, you drill down a small distance and then make an L-turn and drill off to the side. This lets you access oil and gas close to the surface... the stuff that gets lost as a “leftover” in a vertical drilling operation. The trouble is, the oil and gas doesn’t want to come out right away. In order to get it out, you actively pump in a fluid that displaces the oil and gas as well as breaks up the rocks that might be trapping it in place. This pushes it toward the surface, where you collect it. The fluid is called “hydraulic fracturing fluid,” which is where the term fracking comes from. The big problem with fracking is almost always accidents. Sometimes a company spills a lot of the fluid by accident. It’s almost entirely water, but the small amounts of other stuff can be pretty nasty. They don’t want to do that because it’s expensive stuff, they have to pay to clean it up, and it means that fluid can’t go to getting the oil and gas. A big, big problem, is when there are undocumented water wells in an area. Imagine you’re drilling sideways and your path hits a water well. Not only are you now just spilling oil and gas into that well (rather than collecting it), you’re also introducing it and the fracking fluid into the groundwater system. This is a real headache in areas that were farmland for a few hundred years and undocumented wells are more common. There is also a problem of induced seismicity... man-made earthquakes. They tend to be small, but they happen. The idea is, you’re disrupting the rock structures underground, and sometimes you do it in such a way that the area has to settle in again. I am not familiar with this being a major cause of actual damage, but it is an indication of how seriously fracking can disrupt a geological system.",
"I worked as a mudlogger on fracking wells in Ohio. Oil wells back in the day were drilled straight down into porous rock that allowed for fluids to flow. Drill a hole, put in a pipe, suck, get oil. We started running out of those types of oil reservoirs about 20 years ago. You'd hear people worrying about peak oil, and how total economic collapse was going to cause World War 3. Then someone figured, Hey, we've got tons of oil locked in shales. Lets go for that. Shale is a type of rock made of microscopic plates that lock together really tightly. Its water tight. Its also brittle and easy to break. Things dont flow through it though. Fracking is where you target an oil shale layer, drill horizontally through it for about 8000 feet, pack the hole full of explosives, crack the shale and suck out the oil that can now flow through the broken shale.",
"fracking, or hydraulic fracturing, is pumping water and a bunch of chemicals into the ground to break up pockets of trapped oil and natural gas. the problems are that the chemicals can and do travel into things like ground water channels and under ground aquifers (like rivers) and move to other places. people nearby have had these chemicals in their tapwater, and it's come to the surface through the soil. It also often causes leaks of methane, a greenhouse gas. I believe they are better at harvesting the methane than in years past but its still an issue. Methane has even been so concentrated in tap water that the water was flammable. Finally fracking has potentially contributed to earthquakes."
],
"score": [
13,
6,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggf6wh
|
How can completing captchas help Google train data models, when they have to know what the solutions to the captchas are in the first place?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq0ec7i",
"fq0g9vv",
"fq0ltnr"
],
"text": [
"They don't know. In every captcha there are multiple responses to be provided and they only know some of them. If the one's they're sure about are all correct then they will let you through with whatever answer you selected for what remains. They might give the same tests to multiple people to make sure the answers are consistent, but they don't know what the answers are 100% of the time. It's possible they only give the unknowns from time to time in order to keep the accuracy of the anti-bot test high. I don't know the specifics. Just keep in mind that you are providing many answers and that any one of them could be unknown to google itself.",
"When Captchas are run there is always a portion of the images that are known from earlier runs, for example the system knows half are definitely traffic lights. That's how it verifies that you are human since you have to pick all of those correctly. Any other images that you pick in the process get tagged that a real human, since you got all the known ones, thought these images were of traffic lights. After some threshold in number of people doing the same thing, the system is now convinced that those images are definitely traffic lights too so it adds them to the list of known images. This is how Captcha can grow these datasets automatically and is why Google bought them as this is a super valuable tool.",
"It also feeds directly into Google's search algorithms. If you are searching for an image of a traffic light, Google now has 100 more \"certified by a known to be human\" images to show you. Anecdote: when Google was first starting, they had a \"game\" that users could play where you and another random person would be shown two images at the same time and whoever clicked on the \"insert designated word, e.g. dog, car, etc.\" first would get points (iirc). It was a fairly mindless alternative to minesweeper or solitaire back in the day, but am sure it was used to seed Google's image search algorithms. Humans are notoriously good, and computers notoriously bad, at recognizing even basic images. Edit: not quite exactly as I remembered it, and apparently it still exists. Link: URL_0"
],
"score": [
26,
18,
5
],
"text_urls": [
[],
[],
[
"https://en.m.wikipedia.org/wiki/Google_Image_Labeler"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggfyuu
|
How do non-English speaking programmers write code?
|
Are there translations for popular languages or do they simply memorize what the English words do (like print, for, loop, etc.)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq0kb3c",
"fq0mc6v",
"fq2pssk",
"fq2wrjr"
],
"text": [
"We code in English using the English keywords but it's common to see things such as method names declared using a mix of words in two languages: E.g. English and Portuguese: * 'getContaCliente' instead of 'getClientAccount'. * 'ClienteDAO' instead of 'ClientDAO' * 'ContaFactory' instead of 'AccountFactory' * 'Codigos.getInstance()' instead of 'Codes.getInstance()' Also note that while valid, accentuation is actively discouraged and almost never used (except in code comments): * 'Códigos.getInstance()' is irksome",
"Technically some of the words are English words, but ultimately its an entirely different language anyways. An English word may have been chosen to represent some things as keywords (for, while, protected, etc etc) the concepts they represent are distinct from the English word itself. In other words when I see a \"for\" loop I see it as a for loop, it could just as easily be called some nonsense made up word and it would represent the loop as well. Plenty of other steuctures of code don't use English at all (see a Ternary operator). Outside of the language itself the code you write could use methods, variables, and whatnot using whatever names you please. Ultimately they just need to be somewhat understandable by whoever comes along to maintain it. Usually this is English just for convenience as its commonly used. But even in English I've seen come really really bad naming schemes, so take that as you will",
"A decade ago when studied abroad in Taiwan everyone wrote code in English, but comments in Chinese, so I had enough to participate at least :)",
"As a Polish programmer. Well, the thing is you cannot be a programmer without English. Technically there are non English programming languages, but they are not very popular. Knowing at least basic English is must. I cannot imagine not knowing English as a programmer."
],
"score": [
400,
67,
5,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ggguj5
|
How do they "up-scale" animated films?
|
I've seen several examples of animated films (like Disney films) that have been up-scaled for better graphics, but the concept doesn't really make sense to me.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq0tja2"
],
"text": [
"even animated films were still filmed on film. film is already upscale. the downscaled version is what you know of in VHS or DVD form"
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
gggzbx
|
Why do non-touchscreens have that tiny rippling effect when you apply pressure on them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq14m32"
],
"text": [
"They're made from a technology called liquid crystals (that's the LC in LCD). Each individual crystal is very tiny and there are thousands of them arranged in a flat layer to make up the screen. These are arranged in front of colored lights and they can be energized so that they allow more or less of the colored light through to your eye. A picture is made by manipulating the LCs to allow just the right amount of each color through at every point on the screen. When pressure is applied to these LCs by pushing on them, they distort much like a water balloon would when you push on it. When they distort in this manner their optical properties change and they let more or less colored light through than they are supposed to, depending on how much pressure is applied. That's what makes the ripple effect happen around your finger."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggkvq2
|
what’s the “Gutenberg parenthesis”?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq2c4wd",
"fq2gfyl"
],
"text": [
"So for all of human history storytelling was basically ephemeral. That is I would say it to you you would say it to your friend your friend would say it to the next person and so on. If you've ever played telephone you know what the refining and retelling process leads to in terms of information purity. So long comes printing, instead of writing out long hand only the most important stuff. Piece by piece printing becomes cheaper and easier to achieve. It gets so pervasive that you can make pulp magazines and penny dreadful novels. So when writing was rare and reserved mostly for business popular culture was constantly in flux. Most of what was created was lost. and most of what was lost was actually recreated from memory and so subject to constant updating. So pick something horrible, like the current spate of weird \"romances\" like \"taken by a dinosaur\" (seriously it exists look it up), this stuff is being permanently memorialized in print. Take also claims of flat Earth proponents, anti-vaxxers, and conspiracy theorists; all this stuff is being permanently saved and thereby given credence. Now that everybody can post anything on the internet, we're basically back to the spoken word. That is we say what we're going to say and the people who encounter it encounter it but then it all gets lost in the storm. For instance on Reddit if you come late to a post there's a diminishing chance that anybody will even see what you posted. We also sort by novelty or popularity but we can't sort on both. We basically used the universal glut of storage to make storage basically mean nothing. There's also a overabundance of copyright. When a previous artist would write a song and or a play, the writing was a protectable thing, but the individual performances were not. The way you played the song today couldn't be recorded and so couldn't be said to be fixed in the tangible medium. Nowadays you can film or record virtually any performance and then claim other people's actions are infringing on that performance instead of just the original author's authorship. So the cleverly named Gutenberg parentheses represents the idea that for a brief period of time, historically speaking, we lived in an age of stagnation. Everybody in anybody was making a land rush on ideas and getting them permanency at virtually zero effort. Someone can write taken by dinosaurs, and can then use it to pursue anybody else who writes seduced by dinosaurs instead. I mean really but not really. I'm just giving an unreasonable example to make it stand out. So you have to think of it in terms of what we didn't have, what we got, and then what we are now losing. We were in a sweet spot of stagnation. Almost anybody could get published in theory, but in practice someone was still keeping a gate. this is just the same way that anyone can speak but almost anyone who did so had to get and hold your attention at the time. basically the idea is that Gutenberg and movable type and all that stuff created an opportunity to shape culture and make it stick for more than a minute or two. And now the rest of the idea, the clothes parentheses if you will, is the fact that fixing information is now so universally easy that the gatekeepers have lost their role. Think of it in terms of publishers. You used to need a scribtorium full of monks to copy a book. Then you needed a publisher to approve your book and print it for you. Now you can print your own book on demand or even just give out an electronic copy. That middle one filtered but also preserved, before and after there was almost no preservation and absolutely no filter respectively. To some extent the hope is that the land grab of ideas via copyright will be overwhelmedback into obscurity, recovering the freedom and liberties we had before making tangible copies was practical. Basically in the long long ago a company like Disney could not have existed because you wouldn't have been able to reproduce Mickey mouse; in the heyday of intellectual property copyright was extended to the author's lifetime plus 75 years and companies are trying to make it eternal; and it looks like in the time to come soon enforcement will become impossible and we will get our culture back into our individual control instead of corporate control. repeat an infinite combinations for everybody trying to control or filter or validate ideas. It's good for culture, but it's terrible for learning. The parentheses include but they exclude as well. Now that no one has to vet a journal article, every Alex Jones is being treated as a Jonas Salk. But we get music and culture back into our hands as a consolation prize.",
"Before Gutenberg invented the printing press, information was mainly transmitted orally. It was simply impossible to reach thousands or millions with just hand-written copies. So, the introduction of printing brought with it a new way of communication with the masses. Not only education, but also political agendas could now be distributed to the public. The communication changed from „1 person can be heard by about a hundred people or so at the same time“ to „1 person can reach thousands or millions“. This was the opening parenthesis. The era between opening and closing of the Gutenberg parentheses is the era of the printed information. The closing parenthesis is in progress right now as printed information is replaced by information distributed by the Internet. This information is much faster and much more volatile than printed information. And it is now possible to communicate in completely different ways again (everybody has a voice now and can reach everybody). In consequence, the Gutenberg parentheses denote more than 500 years where the printed word was used, and this era now seems to end."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gglln8
|
How do Cloud Storage services like Google Drive make sure your data is safe from a server fail?
|
I'd imagine that the consequences of a data fail would be catastrophic. How does Google keep our files safe?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq20gw4"
],
"text": [
"The same way most stuff is protected. Multiple copies at different locations. Your data is generally backed up more than once, so that if one fails it doesn’t matter, you still have the other one."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ggm1ng
|
How would mail in ballots lead to voter fraud?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq2d66j",
"fq2idlg",
"fq271gb",
"fq2dgh7",
"fq27v6y"
],
"text": [
"We have mail-in voting in my primary. Today I received ballots for 6 people, only two of which actually live here. I guess the other people used to live here. While it's a crime and I'm certainly not doing this, you can see how I could vote 6 times. More interesting is the case of a retirement facility where one \"helper\" in the mail room could take the ballots around to everybody and get them signed, \"helping them\" vote for Hilary Clinton, or whomever. This is a sufficiently common problem that there is a name for it, \"vote harvesting\". It's particularly an issue in places where there isn't usually mail-in voting. If 3% of New York people usually vote by mail and this year 60% do, that's 20 times more work than the state has workers to do. Since the mail in ballots are often not counted for 2-3 days, is it going to be OK to wait a month to know who won? Doubtful. Hiring 20X more workers is a big cost. In a place where there always is mail voting, this is less of a risk and the cost is baked in. But, mail voting isn't common in the US because of the increased expense.",
"Every system of voting has problems associated with it. Our in-person voting system has been in place for a very long time, and we have figured out basically every kind of shenanigan that could be used to game the system. We have also put some safeguards in place to prevent it - but not all. Some pretty standard (internationally) safeguards have been violently opposed by one side (having voters present ID), or the other (automatically registering everyone to vote). What we are talking about with voting by mail is completely changing how 350 million people vote and putting into place a system in 6 months that we had no real experience with. To give you some examples of how this could go wrong: 1. A father is a huge trump suppoerts. His wife and daughter (who goes to college) are not. When the family's three ballots arrive at the family home dad fills them out and mails them in for everyone turning a 66-33 trump loss into a 100-0 trump win (within the family). What are the wife and daughter really going to do about it? Send dad to jail? 2. On a military base 70% of the troops in a barracks are Trump supporters and the other 30% just keep quiet about it. Day of voting the Trump supporters go around the room and make sure everyone filled out their ballots for Trump. 3. Someone takes a look at that 30+ million person data breach from Home Depot. Armed with digital copies of those people's signatures they fill in tens of millions of mail-in ballots. Of course we can see that some people are double voting and that there is fraud, but what about votes being cast by people who didn't bother to vote? How would we ever sort out the tens of millions of bad ballots from the mix?",
"It doesn't really, but the theory is that anyone could intercept the ballot on the way to the person and then mail in the vote for a different candidate. However as well as election fraud they would be committing theft which would be a federal crime.",
"The biggest issue is fraud by the people counting votes. You have to sign your mail-in ballot and if the signature deviates \"enough\" from the signature on your driver's license they are supposed to reject it. The problem is that until you turn 35 the signature on your driver's license is whatever you signed your learners permit with when you were 15. They are aware of this problem and so give vote counters a large amount of latitude to decide if its your signature or not. In practice this results in a system in which one representative from both local parties end up counting the votes and arguing as to which ones are valid or not. Its quite common for that decision to come down who is willing to argue the longest, which in turn comes down to who thinks their candidate legitimately won. This is compounded by the fact that there is no system to automatically notify you if your ballot is rejected. Another issue is something that you're seeing with the Federal Stimulus Payments right now - people move around, a lot. When you use old data to mail important documents those end up going to an old address. A shocking number of stimulus payments are going to the wrong address because of this and there's no reason to think that doing a mass mail ballot based on 2+ year old election data is going to result in anything better. This issue is compounded by the voter signature issue above to allow whoever gets your mail in ballot to vote for you with a decent chance of getting counted if they voted in favor of the candidate whose representatives at the vote counting place are arguing the hardest.",
"The easiest fraud would be one person in the family filling out the ballots for everyone in the family and mailing them in. What are you going to do? Send your family to jail? The other is people dying and the election board not knowing and sending out the ballots and the person at the house filling it out."
],
"score": [
13,
8,
7,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
ggn0xs
|
Why do car manufacturers not design cars with an upgrade path for features which are quickly outdated, eg, GPS, in-car entertainment?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq2ikwc",
"fq2r0pi",
"fq3kywx",
"fq3a9qp"
],
"text": [
"Because they want you to buy a new car if you just updated a few parts you less likely too.",
"My 2016 Kia was able to be updated to have Apple CarPlay. That was a game changer. The built in GPS basically never needs to be updated again.",
"The upgrade path is \"buy a new car\". PCs with an \"upgrade path\" are an exception, not a standard model. Macintosh for the longest time intentionally made it where there was no upgrade path other than \"buy a new one\". iPhones brought this idea back to Apple.",
"It's called planned obsolescence. They really aren't interested in selling cars that have value a decade or two from now. They'd rather people buy newer cars. So they'd be adding cost to the design, and it would hurt, not help new sales."
],
"score": [
37,
5,
4,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggu4rr
|
What do prevents a hacker or a malintented employee to create virtual money out of nothing in bank databases?
|
How does this technology works and how do we know people or banks aren't just creating money without government approval?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq4u2nz",
"fq4tmxf"
],
"text": [
"Double-entry system of accounting. If money is added to one account, it's subtracted from another account. Now, an \"account\" is a broad term.",
"Any big leap in an account value is bound to set off a flag in the system and send an alert to the banks AML/BSA/Fraud departments."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ggubr5
|
Why are most old laptop chargers proprietary
|
I know that a a few newer laptops use usb-c, but most laptops over 5 years old have some weird proprietary connecter, why was this?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq4sxn8"
],
"text": [
"The primary reason is royalties. When companies use tech developed by someone else, such as a specific connector, they have to pay royalties to use it. Often developing your own is far cheaper than paying those royalties."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ggx4tv
|
How is kindle’s screen different from other screens?
|
Is it possible for monitors and phones to have a screen like that?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq59yo0",
"fq5e82v"
],
"text": [
"Kindles use an e-ink display as opposed to the more common LCD or OLED displays found on cell phones. An e-ink pixel doesn't require power to stay in its current state (light or dark). Power is only used to change state from one to the other. So it only uses power to change the display. In comparison, an OLED screen uses power to directly product light and uses the most power to display white. A traditional LCD display uses power to block light. It has a backlight that is always on and uses the most power to block the backlight, so uses the most power to display dark images.",
"The Kindle uses an e-ink display. In such a display, every pixel is a little cell with tiny blobs of ink floating in it. The ink blobs can be made to float at the top to make the pixel appear dark, or at the bottom, to make the pixel appear light. As long as you don't do anything, the blobs will stay where they are, you only need to use a little energy when you want to move them. This way, a Kindle can be completely off and using no energy while still displaying an image. But this comes at a cost: moving the ink blobs around takes a little time, so e-ink screens take much longer to \"refresh\", i.e. to change the image they're displaying. This is perfect for reading: you only want the image to change every couple of minutes or so, and when it happens, it's fine if it takes a bit more than a few milliseconds. But as soon as you want to display moving content, like a video, or just the animations present in OSs like Android or Windows, it becomes really annoying and barely usable. There are a few Android tablets with e-ink, but it's far from a perfect experience. There has also been at least one Android phone with a regular display and an e-ink display on the backside to switch between depending on use case. Current e-ink displays also can't show color, so that's another blocker for mainstream non-reading devices. There are experiments, but nothing that's ready for mass-production, afaik. Just to be complete, quick explanation of how conventional displays work - there are two main types right now: LCD: Liquid Crystal Display. This is what you find in most computer screens, TVs and lower-end mobile phones today. Basically, you have a bright, white background (the backlight), a static grid of tiny red, green and blue dots above that, and then a layer of Liquid Crystals (hence the name) on top. This top layer can be controlled to block the colored dots to display an arbitrary full color image when viewed from a normal distance. LCDs are pretty cheap, and the crystals can change fast enough to display fast moving content. Because of the constant backlight and the not-perfect blocking of light from the Crystals, true blacks are hard to achieve on such a display. OLED/AMOLED: This is found in many mobile phones and quite some TVs nowadays. Conceptually, this is the simplest type of screen - for every pixel, you have three tiny little LEDs glowing red, green and blue respectively. Each of the LEDs can be controlled individually, making a full color image when viewed. These are more expensive than LCDs though, because producing LEDs that tiny is not quite easy. But they have more vivid colors in general, and can display true blacks by just switching the LEDs off. That's also why OLED screens use much less power when displaying dark content, while LCDs basically use the same amount of energy all the time, independent of what kind of image they're showing. Edit to prevent confusion: OLED (and AMOLED) is not the same as screens marketed as \"LED\", see the comment by /u/TDYDave2 below for more info!"
],
"score": [
7,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ggxu9h
|
Where and how does my "deleted" storage go?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq5cqz7"
],
"text": [
"Everything on your storage is, ultimately, stored as 1s and 0s that are somehow marked on whatever storage medium you're using (the exact way depends on what type of storage, but it isn't really relevant right now). The device has to keep track of what spaces in memory are and aren't occupied and what is where. So, the easiest way of \"deleting\" something is to just go to that log and mark that the spaces that were storing it are now unoccupied. As far as the device is concerned, the space is empty and something else will eventually overwrite it. That doesn't really delete anything, though - just makes the device \"forget\" it's there and eventually overwrite it. If you want to be more sure that it's gone, you'd need to overwrite the space it was in with some nonsense data."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ggzi0l
|
How do people take photos of galaxies with 50 hours of exposure? How is it possible to aim at the same spot while earth is doing more that 2 rotations in that time?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq5l1wt",
"fq66xac",
"fq6l4vr",
"fq7t7e0"
],
"text": [
"Hi :-) The stated hours are the combined time of multiple exposures, often during multiple nights. Via software you can then \"stack\" multiple images, increasing details, reducing noise.",
"Combined exposure during multiple nights as others have pointed out and also rotating the telescope appropriately as the celestial sphere turns, keeping it fixed on the one point.",
"An equipment called German Equatorial Mount compensates the earth’s rotation by rotating at the same rate as the earth. The exposures are usually minutes of single exposures stacked together using a stacking software.",
"Iv done astrophotography and what we do is take allot of photos over the course of a few nights and then use software to add all the light from the images together. So when you get 50 hours for one photo you may have taken 50 1 hour photos or 100 30 minute photos the time depends on your equipment, light pollution and personal preference I would normally expose for 20mins at that point where I live light pollution became a big issue. To keep aiming at one spot is normally controlled by two things the mount and a second camera. There are two main types of mounts equatorial mounts and altazimuth mounts. Most astrophotography is done with a equatorial mount. The equatorial mount rotates the telescope around it, the altazimuth mount moves up down left right. I'll focus on the equatorial mount as it's the relevant one. The mount will normally rotate the telescope and camera on it's axis and you need to set that axis up with the earth's axis, now in theory if the mount rotates once a day it should always point at the same thing. In practice this is no accurate enough to really track and object in the sky more that a few hours so that's where the second camera comes in. The second camera will be looking at a star in the area that you are taking photos. That second camera then takes a photo every 10-60 seconds it will then compare that image to the last one it took. When the two images are compared it looks at the light around the star and try to determine if the star is moving in the frame of the image if it is then the software comparing the two images will send a command to the mount to adjust and recenter the star. The reason the mounts can't keep track is because there's is always slight errors in how well we can match the axis of the mount with the axis of the earth's and also the gears that help rotate the mount also have little bumps in them."
],
"score": [
984,
34,
21,
14
],
"text_urls": [
[],
[],
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
gh2zyz
|
Where do the telecommunication companies get their internet?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq629ha",
"fq63u7c"
],
"text": [
"They *are* the internet. They link up to other telecom companies via expensive cables owned by one or both companies, so you can send messages from your computer, through your ISP, through the other ISP, to *their* subscribers' computers. That's it, that's literally what the entire internet is.",
"The internet is a gigantic set of cables. Cable in cities, cables connecting cities, cables connecting countries. Cables connecting continents. ISPs, especially backbone ISPs, run these cables in cities, between cities and between continents. Comcast spent many moneys getting permits and hiring construction crews to bury cables to every house in most cities in the US. Now that they did it, they proceed to rape everyone with prices"
],
"score": [
10,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gh3tpq
|
What are Datacenters
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq68b1f"
],
"text": [
"A place where lots of computer equipment is placed. Looks something [like this]( URL_1 ). They can be [huge]( URL_0 ), housing millions of dollars worth of equipment. Each of those towers is called a \"[rack]( URL_2 )\", and it contains hardware stacked on top of each other. They can be computers, batteries, switches, routers and all sorts of equipment, all of which is made in standard sizes that fits into a rack. There's going to be all sorts of auxiliary hardware as well -- air conditioning to keep the machines cool, security cameras, access control to the door, connections from internet providers, fire suppression, power backup systems, etc. There's typically raised floors and drop ceilings to make running cabling easier."
],
"score": [
5
],
"text_urls": [
[
"https://si.wsj.net/public/resources/images/BN-WZ757_GOOGCA_GR_20180115190935.jpg",
"https://www.abb-conversations.com/wp-content/uploads/2014/02/DataCenter-Infrastructure_Network-Server-Room1.jpg",
"https://en.wikipedia.org/wiki/19-inch_rack"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
ghbzvr
|
How different parts of a PC work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq7ws6i"
],
"text": [
"Do you want this ELI5? or \"ELI I'm building a computer and actually need to know what components do\" for that go to /r/techsupport"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ghmoue
|
OData and Rest APIs
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq9mn2g"
],
"text": [
"For an example, let's say you have a database of books you want to make available over an API. If you GET /books, you get a listing of all the books. If you POST a book, a new book is added to the database and you get back its book ID. If you GET /books/ < id > , you get the individual book with ID < id > . If you PUT to an existing book ID, you can edit it. .... This is a REST API and it's pretty useful to put between a user interface and a database. OData is an extension of the idea to allow you to for instance: * ask only for a particular field of the book object. GET /books(1450)/Title * request a book together with its linked author object. GET /books(1450)?$expand=author * request all Books published in May of 2014. GET /books?$filter=Published le 2014-05-31 and Published ge 2014-05-1 These more advanced capabilities in the API allow the user interface programmers to better and more easily answer the questions users might have."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ghnp2v
|
How do YouTube to Mp3 converters work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fq9q9m6"
],
"text": [
"YouTube and any other streaming service send down videos in a series of chunks that are seamlessly played together. An application can take these chunks, staple them together, take only the audio portion, and give you an MP3 as a result."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ghr2fi
|
How do cores, i5s/i7s/i9s, different GHz, and 16/32 GB of memory affect a computer performance when working together?
|
I want to get a new computer because I’m an educator and I’d like to start designing a website, making video content, writing long documents, photoshop, and other content creation. I’m looking at a MacBook but the research on how all of the cpus work with cores work with ghz speed work with different memory sizes is making my head spin. Please, ELI5, show me how all of these things work together as if they were one functioning system. All I can find are articles that explain each separately, but not how each impacts the other. Thank you!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqaa9vb",
"fqahu4f"
],
"text": [
"Ok so the cores are part of the cpu. The cpu is, as the name says, the central processing unit. It processes tasks. But to process those tasks, the cpu often needs data to work on. But accessing data from the harddrive is slow. So the data that is needed for processing a task is stored in the memory storage (RAM), because it is build in a way that access is faster. More memory space means that more data can be read fast, which is helpful for large processes like loading a large ampunt of data (like in a gameworld). If you have more questions, please ask.",
"The CPU is the brain of the computer and the RAM is the lungs. On a very general level, more RAM will allow you to do more things at once (open a ton of tabs, have Photoshop and After Effects and League of Legends open at the same time), while the CPU will allow a given tasks to be processed faster - something you'd notice if you were trying to render a video or perform a similar \"heavy\" process. \"iX\" is the Intel processor model name (higher is better) and GHz is the speed of each processor core. More cores and faster are better, but you can compare which processor will be faster on the whole by just comparing prices. A very loose way to think about it is GHz speed x # of processor cores. Even base Macbook Pro models are pretty decent these days, so I'd recommend something mid-tier for the processor and ideally 16GB of RAM for stuff like programming or fucking around with Photoshop. If you have Chrome open with 25 tabs + Photoshop, you want enough RAM to breathe comfortably. If you're planning on PC gaming or more intense video creation, you need to look at graphics cards as well, which are kind of like CPUs that specialize in parallel operations - i.e. stuff like rendering images in real time."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ghwg0z
|
Why do VR games need so much more power to run?
|
One thing that's throwing me for a loop is that VR games run at fairly normal resolutions. For instance, the oculus rift S only has a 1440p screen, it's the same 2560x1440p resolution. A GTX 1070 or higher can run most games at that resolution at 90fps or above. So with worse lighting quality what makes these games so demanding to run with the same hardware?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqbecgj",
"fqbg37f"
],
"text": [
"To achieve an authentic 3D effect, VR games need to render two separate images for every frame, one for each eye. So straight off the bat you need nearly double the horsepower for the same resolution on a single monitor. Also there is a lot of extra positional tracking data which is being processed simultaneously.",
"Former game developer here, The biggest problem is all the overhead in rendering the scene twice. You have to transform all the geometry of all the polygons in the scene, twice; you have to cull and occlude, twice; you have to UV map your textures, twice; you have to compute all your lighting, twice; you have to alpha, raster, dither, and anti-alias, twice. Bigger screen geometry has nothing to do compared with having to do the same work twice. A bigger screen simply means more rasterizing, and that's already one of the faster things a GPU can do. And in the end, you have a novel effect that really isn't that much more compelling than rendering a 3D projection onto a 2D screen once. You can get an adequate immersive effect by having mono vision in an enclosed headset simply because it's like putting blinders on a horse, and you're the horse. If you were told it was VR, you might not even be able to tell the difference. VR is a novelty that has been popping up since the 80s, again and again. They even tried to bake it into panel televisions in the early 2000's, and that went over like a lead balloon. The industry is mostly not interested in the technology because the visual effects are twice as expensive but not for twice the gain, but, as you've noticed, you definitely lose color and lighting - that's always been a problem inherent with the technology. The major studios would rather deliver you one spectacular render 60fps than two mediocre renders that don't add to the gameplay. So the technology will always remain niche. It's a novelty. And what no one is willing to admit is there is a big liability issue because no one knows what VR does, long term, to the young, developing minds of children. Sega developed a whole VR console, it was to replace the Genesis (it might have been what turned into the 32x), and the testers noticed quite a few extra fender benders in the office parking lot. Legal pulled the product because they didn't want to get sued for harming a child, and there is no way to ethically perform such a study. We do know it does have lasting effects on the brain of adults."
],
"score": [
7,
4
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
gi0qqm
|
What is CPU hyperthreading/multithreading and how does it benefit me?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqc34uz",
"fqbxn0g",
"fqbypwn"
],
"text": [
"Someone commented this awhile ago and it stuck in my head. Hyperthreading is just like giving a worker 2 conveyor belts to complete said task instead of waiting on materials coming down one conveyor belt and just standing there waiting for the next. It benefits you by your processor completing tasks faster, which gives more performance.",
"Think of a CPU having roads. Each core is simply a 1 way road with constant traffic. For example, we have a 4 core CPU so 4 single lane roads for traffic to travel down. The more cores you have, the faster the cars can keep moving. Now add hyperthreading to those cores (roads) your roads turn into two way roads, so now we have 8 lanes of traffic. This increases throughput of traffic! In the very simplest of explanations, it helps you do things quicker. (but not everything) Hyperthreading has specific use cases where it is EXTREMELY beneficial, and other times detrimental to a degree.",
"A lot of time and effort have gone into making CPUs faster by executing instructions in a different order than the program specifies. This is advantageous because different instructions use different parts of the CPU to execute them and they take different amounts of time to run. By reordering instructions and even running some at the same time (if they don't collide within the CPU) you could improve performance. At some point the decision was made that these features could be tweaked to let a single CPU run like a dual core CPU, or back in the old days a motherboard with 2 CPUs on it. The downside is that not everything in the core, like the math unit, is duplicated - while the two threads can take turns using it, if they both want it at the same time one thread has to wait just like in the instruction reordering scenario. However in the grand scheme of things it still usually adds up to the CPU doing more work since more parts of it are in use at a time. A CPU doing more work finishes its work faster, etc. That's good. Enabling hyperthreading isn't quite the same as a CPU with double the number of cores, but compared to hyperthreading off when the CPU is running at maximum power you can get most of a doubling of work done. Of course, the usual rules of many CPU cores still applies... If a program can only use 4 cores and you have a 4 core (8 threads) CPU, enabling hyperthreading won't speed it up."
],
"score": [
10,
9,
3
],
"text_urls": [
[],
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
gi1nch
|
why does having a long story before a recipe help websites get better search engine results?
|
Whenever I'm looking for recipes online there is invariable a long story about the author's family and which family members like this dish and which ones do not. I'm sure I'm not the only person who thinks this is vey uninteresting and just wants to get to the cookie recipe but I've heard that doing this gives websites better chances of turning up higher in search results. Why do these stories improve search rankings? Who decided to set the settings that caused this?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqc521e",
"fqcm5bi",
"fqcpzhj",
"fqc31c0",
"fqcorj4",
"fqdjai2",
"fqdat25",
"fqd7sc1",
"fqcxz6g",
"fqcpmr8",
"fqco6hn",
"fqdfh4o"
],
"text": [
"Another aspect of this search engine optimization is simply content depth and key word frequency. The exact details of search engine algorithms are closely guarded trade secrets, but we know that page ranking has to deal with two competing problems. You want sites with lots of on topic content to be ranked higher than sites with less content. But at the same time, you don't want people being able to fake their way up the rankings with a bunch of nonsense \"word salad\" of keywords. So search engines count keywords and content depth but they also try to eliminate sites with keyword nonsense. A bare recipe doesn't read like valid English to some methods of analysis and is \"shallow content\". Someone's family history with a recipe reads better, increases content depth and still allows for repetition of keywords.",
"One factor is repeat content. Most search engines tend to view identical or near identical content as a single result, so that they dont serve up a dozen results that are virtually the same. As a result, only one of those identical pages will be considered the \"authoritative\" source of the information, and itll be the only one that gets served. If you're posting a recipe, the likelihood is that your set of ingredients for a dish wont vary much from the next guy, and you all run the risk of being collectively lumped together. If you include a long and unique story introducing the recipe first, you're much less likely to be considered duplicate content, and thus more likely to show up in search results.",
"They don't do it for search engine optimization. Well, not entirely anyways. Recipes aren't copyrightable. But, articles about a recipe are. So, everyone writes a long article talking about their recipe - then they can cease-and-desist anyone who copies that recipe as infringing on their article. And, it's not just recipes. For just one other example, magic tricks aren't copyrightable, so Penn and Teller write little scenes that go with their tricks, so that if someone steals the trick, they can sue them. [This is one of the tricks they specifically wrote a story to for just this reason.]( URL_0 )",
"It improves retention time, and thus makes it look like people enjoy or are getting more out of the website.",
"Google search results are a good way to attract readers to a piece of content but getting people to subscribe is considerably more valuable. There’s some good informative answers here but there’s more to these stories than search results. There’s also something to be said for reaching a target demographic and creating relationships with your readers. There are some people who enjoy the transparency into someone else’s daily life. This demographic may be more likely to subscribe to your newsletter and return over and over. Edit: You know what else is great for SEO? COMMENTS. The more comments a page has the higher it will rank in search results. Connecting with readers in a personal manner is a pretty good way to have them comment on your page.",
"Ok I've went through the responses and some posters are touching on it but no one hits the nail on the head. & nbsp; **First, a couple of things that people get wrong:** & nbsp; **1.** It has nothing to do with copyright, Google will outright penalize and not show duplicate content in it's search results. The whole Google update (Panda) was about this. Content rewriting is still a big thing. Not spun content by some AI (although it's used in some cases), but content rewritten by a real writer. & nbsp; **2.**Word count is a thing of the past. + what would stop you from putting all that text below the actual recipe? Google's algorithm has gotten much better and there is no word count \"sweet spot\". Got a page about Ancient Rome? Write 20k words. Got a page on \"how much time I need to make a hard boiled egg?\" - The answer can be fit in one sentence. Furthermore, Google now uses URL_0 markup, it's a way to give pointers to Google what the content is about. One of those mark-up parameters is the recipe mark up. On top of that, most of the Google index is mobile-first now, which means mobile pages get evaluated first and content under accordions or \"show more\" buttons is not treated as hidden (malicious) text. & nbsp; **3.** Not that much to do with topicality as well. Think about it, why would \"My grandmother used to make this for Scottie after a whole day of playing outside\" would add to topicality? If anything you're talking about something only semi-related & nbsp; & nbsp; **Reasons why there's a bunch of text before a recipe** & nbsp; **1.** Users need to spend more time on the website. The more time they spend the more chances you get for making them sign up for a newsletter, buying something or even just seeing ads. Not all adds work on a CPC (cost-per-click) model, some adds will work on a CPM (cost-per-mille) model, which means you get paid for every 1000 impressions on an ad. This is also the reason you need to scroll past the first 1/3 of any page on the internet. & nbsp; **2.** Google uses engagement metrics for rankings - let's say you have a recipe about Shephed's Pie. People google \"shepherd's pie\" and land on your website. After 10 seconds they realize that your recipe is bad, go back and click on another result. This signals to big G that your page didn't really answer the query that the user had. If users go back after 45 seconds and click another result, it's still a bad signal, but not as bad as the first one. & nbsp; **3.** Last contributing factor is that it's an artifact from times gone by. Some 3-4 years ago, word count and keyword density were all the rage. Writing pointless intros was the rule, not the exception. If you look at the top3 for most common recipes, you will see huge sites dominating consistently. These recipe pages will have < 500 words of text and go into the recipe right away. There are other factors for this, like sheer website Authority, but you will see a gradual shift towards pages that answer the query directly. It's not phased out completely from smaller sites because of reason #1 above. & nbsp; & nbsp; Hope this answers your question",
"I haven't yet seen \"the people writing the recipe enjoy blogging, write the posts for people who enjoy reading them, and want you to read what they wrote\". Not everything is carefully calculated to manipulated the Google algorithm.",
"Search engines count how long someone spends on a page. A long page with rubbish means people spend longer on it. Google has actually ruined a lot of good internet content.",
"Basically, because Google can’t hire millions people to read through every page on the internet, so they have to use algorithms instead. Google’s algorithms use certain markers to figure out what a website page is about and whether someone searching on Google wants to see it. There are a few markers that they use, but the most important ones are: 1. Keyword relevance 2. Keyword density For each page, google looks at a word or phrase that summarises what the page is about (e.g. “fruitcake recipe”). This is your page keyword. If you google “fruitcake recipe”, that’s a tick in the relevancy box. But Google also wants to see that you really know about the topic. Are you the best page for it to highlight when someone is searching for a fruitcake recipe? Do you know more than any other page about fruitcake recipes? The way to show Google you are is by putting plenty of the phrase “fruitcake recipe” in the page, show Google you’re a really good source of fruitcake recipe information, going really in depth into the content. Just spamming the words “fruitcake recipe” isn’t any good though, Google is pretty good at figuring out spam content vs real content, so you’ve got to write yourself a real blog post that mentions it a lot. There aren’t that many blog posts to write about fruitcake recipes though, so you write a blog post about how your grandma passed down the recipe on her death bed etc etc. Well now Google thinks that you’re the best darned content on fruitcake recipes and pushes that content right up to number 1 of the google search page (a simplification, but you get the idea). The algorithms work really well for most things, blogs and information articles especially. They are very good at answering questions and giving you the information you need, something Google was designed for, but they mean that certain websites have to jump through disingenuous ‘hoops’ to make sure they’re seen (such as a 600 word blog post on how fruitcake recipes make them feel). There are plenty of recipes that DON’T do this, but you never see them because they’re on page 9 of Google searches. Thus it becomes a self fulfilling prophecy.",
"If you're looking for information, then long, well written content is usually better than short. My understanding is that somewhere around 2000 words of relevant content is about the sweet spot. Obviously nobody knows for sure, but from the (around 2000 word) articles that I've read where people have trialed different word lengths it seems to be the length that does best. & #x200B; For what ever reason, Google applies this formula to recipes. Why Google does this is, I don't know! It can clearly tell the difference between recipes and other content. Surely they can figure out some other metrics to assess the 'usefulness' of a recipe. Maybe the people who go through the effort of making up a back story are also the people who can be bothered spending time making sure that the recipe is good? But on the other hand, people prefer non-back story recipes so you'd think they'd favor the content that people want?",
"To rank better in search engines they need to have at least 800-1200 words that aren’t fragmented words (aka recipes).",
"A lot of these responses are really overthinking this talking about SEO and google’s algorithms and whatnot. It’s really a lot simpler than that. First, a lot of these recipes are on blogs and those bloggers like to imagine they have followers who read and care about that content. Second, the longer the page the more ads they can fit."
],
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[
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gi3bbm
|
if I skipped an update and waited for another one, does the 2nd update's file size become bigger?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqcchcr"
],
"text": [
"It depends on the type of download. Some downloads will re-download the entire game (rare nowadays, but common in “electron” apps like Discord and Twitch) Most downloads will only install what has been changed since the current version. This means, yes, the file size could be bigger."
],
"score": [
3
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
gi67oy
|
How are Bitcoins 'mined'?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqcutvg"
],
"text": [
"In a Blockchain, transactions are stored in blocks and chained together. The chain is created by the last block in a chain containing a hash of the previous. A hash is basically a small number/string of characters created based on an input. The string is created by a hashing algorithm. Hashes are usually easy to calculate but hard to reverse, so it's a one way thing. In a Blockchain, rules are created to dictate how the hash should start and this changes with difficulty. Let's say for example the hash needs to have 10 '0' characters at the start to be valid. If you hash something you always get the same result. Thus if the hash does not start with 10 '0' characters a miner will have to add a random string to the end of the block and then hash that to see if it is acceptable. When a miner finds a string that can be added to make the new block start with 10 '0's it's published to the network of miners and accepted as the next block. The miner that finds the block is rewarded with an amount of BTC as a thanks for the work. Also each transaction has a small transaction fee. The miner that finds the new block may also keep that. That's a basic example off the top of my head anyhow. Happy to clarify further. Oh and I also accept that this is not a perfect response. It's designed to be an overview to get the idea of how things work."
],
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3
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|
[
"url"
] |
[
"url"
] |
|
gicxsk
|
How does registering a domain work? Why does it cost money to register an unused domain, is there a big database of domains owned by one company?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqdwwt7",
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"text": [
"You're not buying the domain from someone. You're paying for the service of publishing your domain to maintain the record and push to thousands of dns servers worldwide.",
"At a super high level: The entire internet is controlled by one organization - ICANN. They are the organization that decides what the top level domains (things like .com, .org, .edu) are. They run a seperate organization, called IANA, that controls (among other things) the master DNS servers, which serve as the master 'address book' of the internet. ICANN has sold/given the rights to register domains for the various TLDs to specific organizations. For example, VeriSign has the exclusive rights to register .com domains. What this means is that they have the exclusive right to update the DNS servers with the domain name to IP address mapping for .com (and this mapping is what allows a domain name to point to a specific webserver). These companies then allow resellers to sell unassigned domains to end users. When GoDaddy sells you a .com domain, they can do this because VeriSign allows them to, and updates the DNS for GoDaddy. So, it costs money to register a domain because each one of these companies requires revenue to operate. GoDaddy needs revenue to sell you the domain, VeriSign needs revenue to write to the DNS, IANA needs revenue to maintain the DNS, and ICANN needs money to oversee the TLD system."
],
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4
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|
[
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[
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|
gid50c
|
how does a mouse sensor work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqdukxf"
],
"text": [
"Modern mouse sensors are actually pretty basic. An optical mouse is basically a red LED, which bounces light off a surface and into a CMOS sensor (not to be confused with a CMOS inside a computer) This CMOS is basically a camera. It takes the image and compares it to the next one. Using this data, it can work out how far, and in what direction, the mouse is moving. This can happen hundreds or thousands of times a second. Most gaming mice have the ability to change the amount this happens, allowing for faster, or slower but more accurate movement."
],
"score": [
10
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
gidq6z
|
What’s the difference between a wifi extender and mesh network?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqdywuw",
"fqe4wmm"
],
"text": [
"Typically, a WiFi repeater is pretty dumb and just repeats everything. A mesh WiFi network is intelligent in only rebroadcasting what needs to be rebroadcast in order to extend the reach. In addition, Mesh networks can be managed in a single interface, whereas repeaters need to be configured separately to work along with the main WiFi access point.",
"Imagine a party. And you want to get a message from one side of the party to the other. Your wifi just shouts out \"John, John!\" and John either is in range to hear or not. Wifi repeaters/extenders are just dumb repeaters. They don't care about what's happening, they just repeat what they hear. So when they hear \"John, John\", they then shout out the same thing from where they are. So you get \"John! John! John! John!\" If you only have one repeater in a quiet party, that's okay. But as you add more and more repeaters, it quickly becomes a mess and NOBODY can communicate effectively because of all the wifi's shouting \"JOHN! JOHN!\" as loud as they can, stomping over even the original message. A mesh network is more intelligent. It does the exact opposite of what you think it does. Mesh networks are able to talk to \\*each other\\* (they have to \"speak the same language\" which usually means being from the same manufacturer or conforming to a wifi mesh standard). And in that, they are able to help each other. They literally shout \"EVERYBODY QUIET! GEORGE IS TRYING TO SPEAK\", and then all the mesh points quieten down so that you can hear George say \"John?!\" from across the room. Repeaters are household items that end up in shouting matches (because your neighbours all have wifi too, so it quickly becomes just a shouting match over each other) and though they might make your wifi go further, they decrease EVERYONE'S (including yours) wifi speed as everything needs to be shouted, get misheard and has to be repeated. Mesh wifi is used more often in commercial areas, in arenas, schools, hospitals, workplaces, etc. where the radio waves are relatively empty \\*except\\* for the mesh network, and where you need the mesh network to work reliably and be fast (not just have great coverage), and where you can join lots of wifi points together. Repeaters are cheap junk that makes everyone's wifi worse but will work with anything. Mesh is the professional version that tells both wifi points and compliant devices (e.g. smartphones) to power down and not shout so loud if they don't need to. But it only works well when you buy compatible wifi points, and usually best from one manufacturer."
],
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5,
4
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|
[
"url"
] |
[
"url"
] |
|
gie7z3
|
How come when you are watching cable television and the show you are watching is about to come back on you sometimes see a split second of a cutoff commercial?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Different TV stations show their own commercials for local stuff, like the local news channels, other shows they air, or local events to give some examples. But the feed they are showing for the main show(s) are from some other feed they get that might be nation-wide or other larger broadcast areas. The local station will insert their own ads over the ads in the main feed, but sometimes the timing isn't exactly right and for just a split second you can see the ad from the real feed as it finishes and goes back to the real show.",
"In Canada, we have a thing called 'simulcasting', where the Canadian stations are allowed to substitute their commercials for the American ones when they are playing the same show. So that happens fairly frequently. In fact, last night, we were watching *Wheel of Fortune*, tuned in to the US station, and about five minutes in, it was switched to the Canadian station, which was showing a completely different episode. We were sitting there for a few seconds, wondering what happened to Barry and Madeleine (two of the contestants) before we clued in to what had happened.",
"As others have explained, these are \"local insert\" commercials. CNBC transmits a national feed with its own commercials baked in. Your local cable company will take that feed and overlay its own commercials before sending the broadcast to you. But the cable company's timing might be off by a second or two, causing it to overlay its commercials too early, so when the cable company's commercial ends, you see a couple of seconds of the national feed commercial before the show resumes. If you are watching on the CNBC app, that's simply another \"cable company\", overlaying app-specific commercials onto the national feed, even if the \"commercials\" are just screens saying \"Commercial Break in Progress.\" This is so that CNBC can sell targeted ads, where every viewer gets a unique ad.",
"I actually work in a TV station so I can answer this. So if you see a part of a commercial and then it immediately cuts to another one, those are the parts of the break segment where local advertisement is run and 99% of the time, those need to be triggered manually. And those always come in with about a 2-second delay that has to be compensated for by the control room operator. So there is a very good chance that their timing isn't perfect and that leads to those jarring cuts between two different commercials.",
"Yeah, this is exactly what I do for a living. National or network broadcasts play network commercials and we insert cue tones into the signal (remember when CNN use to opening broadcast quick DTMFs when breaking into commercial? We URL_0 .that but on a separate audio channel (or imbedded data these days) to instruct affiliate stations to run local content. We beep back to national. When the locals are out of step time wise, you get those gaps. For industry types, I'm one of the more primary contacts for DEMs if you have them in your uplink.",
"These days there is also technology to run \"over the top\" or OTT commercials built into your set top box. Your set top box is collecting data about what you're watching, and that profile data can be targeted with ads. I can pay your cable provider to show my ad to \"people who usually watch Survivor\" or whatever, and I can target you with ads any time, even if you're not watching Survivor right then. So you might see a different ad to your next door neighbour even if you're watching the same show at the same time, and there might be seams from time to time between the OTT ads and the regular ads. Smart TVs collect and sell these same profiles but for everything that you watch on that TV, btw. They even track what video games you're playing and what porn you're watching.",
"We get this in Canada all the time; they lay Canadian ads over the US ones for major sporting events, for example.",
"Oh hey, I see a lot of good answers here and they're all very close to the correct response, but I work for a large cable company and can tell you that there's a little more going on behind the scenes. When commercials play on TV, there is some way that the distribution companies know that there is a commercial on. This could be a sound that is outside of human hearing range (that gets stripped, for obvious reasons, as it flows through the cable company's signal chain), or it could be a schedule, or someone sitting at a desk watching a feed that is intentionally delayed. At the cable company, contracts are exchanged to insert commercials over the \"default\" commercials that certain channels are using, and the channel providers usually tell the cable companies when they can and absolutely cannot insert a commercial over their content. The systems that are used to overlay commercials are usually automated, although there are some commercials that have to be manually inserted in order to meet the requirements of a certain order (political ads are usually the worst about this). Now, what causes the cutoff is usually one of a few flaws with the way the substitute commercials are either distributed or inserted. The biggest factor is time. Inserted commercials are usually ordered in bulk to go in at any point during a regular break. It may be requested to put the commercial over another commercial that is slightly longer or shorter than the one it is supposed to replace. Additionally, there may be a miscommunication about when the commercial is supposed to air, either from the company that provided the ad, or the station that is allowing the replacement, and this happens more often when manual scheduling is used instead of the tones I mentioned above. Finally, and what I see most often is that the system that inserts the ads loses time sync with the channel for some reason. This usually happens when the ads are stored locally on your DVR (yes, they do that) and are scheduled to overlay at a certain time. Your box may have the right time, but the feed could be delayed for any number of reasons - usually the delay in this situation comes from the time it takes for your box to decode the video. I can explain more of these points or provide more examples if you want, just let me know. Source: I helped implement an ad-insertion system at a major TV provider, and spent a number of years working on it."
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|
gifa1x
|
How was graphic design done for something like a board game or a book cover before modern computer software was available?
|
I suppose I'm referring to things that don't look like they were just hand drawn. For example, take Monopoly boards from the 1950s or 60s. How did they design and reproduce the symbols when they didn't have digital scanning and things of that nature?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqe8i2x",
"fqeb0qc"
],
"text": [
"With moveable type. It was invented by Gutenberg, in 1450. Before that, it was wood block and engraving. Everything has only been digital in the past 20 years or so.",
"Chances are you haven't seen something that was hand-drafted rather than hand-drawn. Using things like a t-square and various french curves, a draftsman can create smooth lines and curves without messing things up. If he does mess them up he can start again, trim off excess with an xacto blade, etc; and then once he has all the constituent pieces made right, send the prototype off to a printing company that will take that, make it a series of negatives for printing, and run it through various presses with movable type to mass produce them. I studied the drafting more than the printing, but if memory serves they would measure out the proposed board size and print a piece of paper that was big enough to have some to wrap around the sides, then glue the ends after wrapping them around to the bottom and cutting off excess."
],
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3
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"text_urls": [
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|
[
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[
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giier1
|
How do NASA scientists know that a spacecraft is completely air sealed before it goes into space?
|
Technology
|
explainlikeimfive
|
{
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"fqeqekl",
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"text": [
"The same way we test any other pressure sealed system, raging from big tankers to tanks, to the gas pipe systems. Every valve and opening is sealed, then we pressurise the system, if the pressure doesn't drop then it is sealed. Once they close the door to the spacecraft, they can pressurise it and check whether the pressure stays stable.",
"NASA engineer here. First, only manned spacecraft are sealed. Robotic spacecraft are purposely vented. This reduces the structural loads and lightens the primary structure. But it means that all your electronics must be tested at vacuum and it impacts thermal designs. (Except for the Russians, they just seal all the electronics in a big, pressurized vault. They pay on mass-to-orbit, but it simplifies ground testing.) For manned missions, during design and preliminary testing, you just pressurize the vessel with the same pressure drop from inside to outside. e.g. Say your spacecraft is designed to operate at 4.3PSI (the operating pressure of a NASA space suit), but you're at sea level with an ambient pressure of 14.4PSI. You just pressurize the suit to 18.7PSI to test. However, at 4.3PSI, you'll be running the suit at 100% oxygen. This is where Apollo 1 ran into an issue. They pressurized the capsule to 16.7PSI, but at 100% Oxygen for a ground test. At those oxygen levels, things that normally smolder, burn rapidly. Things that normally burn, explode. The Apollo program completely overhauled their atmosphere management after that accident. Let me know if you want to learn a bit more (like how astronauts can get the bends if they're not careful going out on spacewalks, perhaps).",
"The cool thing here is NASA actually tells us exactly how they do all their testing. Because they work for the public they tell us how they do testing in details in papers for free on the internet. They may use a giant vacuum chamber with heaters and chillers to make it like space. Or they may create custom setups to make the difference inside and out about the same as space. They will do this hot and cold, over and over. That is called environmental testing. They will make the temperatures more extreme and the vacuum stronger during testing than real life. That is called a safety factor. Basically everything leaks. It may not leak fast. In fact it may leak so slow that air doesn’t really leak out fast enough to measure. So they use helium gas to look for leaks. Helium is a really tiny molecule that is specially good at escaping. Then detectors will see how much helium is leaking. NASA will have rules for how much leaking is Ok. None would be great but when it comes to helium and doors that open and close in space there may be some. And that is find. Beyond ELI5 For reference if you want to read more here is a document on designing their hatches used: URL_0 And here are some testing standards: URL_1 TlDr; NASA uses a camber or other setup to produce vacuum a little stronger than space. They also include heat and cold. Inside they put helium because it gets our easier than air. Outside they check for how much helium gets out.",
"You put the craft into a building, suck all the air out of the building, then watch all the pressure guages. ...but the first step is very careful assembly.",
"Retired NASA engineer/Shuttle manager here. For the shuttle, we used air pressure tests at MULTIPLE points during processing, with a final check coming in the last 30 minutes before flight. The commander would move some switches on his left that over pressurized the cabin above sea level, hold it there, then he would depresurize it which would sound the master caution and warning that we would then clear/reset, then re-pressurize to flight PSI and hold there till we launched.",
"I once worked for a company that had an old Apollo capsule. There were so many inspection stamps on the door locking mechanism and the ratchet handle it was hard to see metal."
],
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"https://standards.nasa.gov/file/13775/download?token=7NfyuMRs"
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}
|
[
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[
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|
gilajy
|
Is there an eventual limit to how fast we can wirelessly move data? If so, what is that limit?
|
Obviously wired connections will always be faster than wireless, but is there hard limit to moving stuff wirelessly? Not attached to equipment, but in relation to how fast the signals can move through the air / how much they can carry through the air? I don't know any better wording. Sorry!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"text": [
"The maximum speed anything can move in this universe is the speed of light, which is electro-magnetic radiation. Information via wireless communication is transmitted in this format. So, the speed of light. If you're asking about *bandwidth*, i.e. how much data can be transmitted within a period of time, that's another matter altogether and changes depending upon the advancement of technology, but [175 terabytes per second is apparently the record for a wired connection.]( URL_0 ) (thanks to [macncheesee]( URL_1 ) for the correction that this is not wireless, as OP asked).",
"Somewhat. The closest thing we have to such a limit is called the [Shannon-Hartley theorem]( URL_0 ). But that bounds it with respect to signal power (assuming noise is fixed), if we increase the power going into the wireless transmission we can increase this bound. Or we just increase the electromagnetic bandwidth (range of frequencies) of the signal. But Shannon-Hartley is really only a thing because of noise. With no noise (random electromagnetic signals that come from all sources) that bound is infinite.",
"Nothing can move faster than the speed of light and all RF moves at the speed of light already (within a vacuum). Bandwidth and getting through all the other pieces of equipment are the real challenge (wireless receiver, processor, etc. Sidebar: there are two limits to how “fast” data moves: bandwidth and throughout. Bandwidth is how much data can pass through at one time while throughout is how fast it goes. The professor of my first IT class out it better than anyone else I’ve ever heard: Imagine a highway. Bandwidth is how many lanes the highway has. Throughout is the speed limit of the highway."
],
"score": [
14,
6,
3
],
"text_urls": [
[
"https://theworldoffact.blogspot.com/2018/10/what-is-fastest-internet-speed-ever.html",
"https://www.reddit.com/user/macncheesee/"
],
[
"https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
gin5wm
|
Why does ‘turn it off and on again’ work so often with electronics?
|
Seems to be the go-to response to tech issues to the extent where it’s used as a joke response to any issue. From a programming perspective it shouldn’t help as nothing algorithmically changes, so what is physically happening?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqfl568"
],
"text": [
"Programs rely on what the state of the system is, especially the data stored in short term memory (RAM mostly) to operate correctly. If that state is screwed up somehow, the easiest fix is to reset everything to a default state. Imagine closing your eyes and walking from your house to some house you know of a few blocks away. You might count 3 blocks forward, turn left, 1 more block, then fourth house on the right. If you miscount for some reason you end up at the wrong house. It's also hard to fix this mistake, since all you know is youre in the wrong place, but you dont know where that is. Resetting a computer or other similar electronic is the same as teleporting you back home so you can try again, but more importantly, you now know where you are. Edit: mobile spelling D:"
],
"score": [
19
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ginmwy
|
Why is there such a fuss going on right now with 5g cell service? How does 5g work and what are it's benefits/drawbacks?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqfnxsx",
"fqfo77r",
"fqfnz1b",
"fqfpli5"
],
"text": [
"5G is the newest \"update\" to the service we currently get on our cell phones. It's faster (almost 10x as fast in some places) and covers a wider area. That being said, it has not yet been perfected and dropped signals are common. Also, there is a conspiracy theory that 5G created COVID-19 which is wrong.",
"The fuss? People are dumb, panicky dangerous animals. Somewhere along the way, some dipshit posted some crap about 5G being OMG 60GHZ RADIATION. And now every person with antivaxxer intelligence levels and critical thinking skills things its going to cause everything from autism to male pattern baldness and that it's actually going to be used to activate the control chips coming from the mandatory covid19 vaccination. Benefits? Faster mobile data. Drawbacks? Only one I've heard that might be an issue is that one of the frequency bands used may interfere with a similar wavelength used to monitor the atmospheric moisture levels that are used to predict weather systems.",
"Is not about the benefits/drawbacks at all, some people said that 5g towers spread Corona as a joke and some idiots belived it and started to spread the stupidity like anti vaxx propaganda. Since that happened a lot of people are starting to look up what 5g is",
"Another benefit of 5G when implemented as designed is better cell battery use. Right now it's being implemented as 2.4GHz in places but the ideal uses a different higher frequency. Problem is that frequency doesn't travel through things so well, so instead of large towers serving several miles around the idea is to install tons of smaller units more locally. Your phone tries to use the lowest-power signal it can to maintain as good a connection as it can, and 5G's \"tower\" setup will allow your phone to push less power to the transmitter and still keep good signal. The drawback is well... Having to place all these little access points everywhere in order to implement it fully as designed rather than just strapping new hardware to existing towers and calling it a day, at least in cities. The big fuss revolves around several conspiracy theories based on pseudo-science, half-truths, and/or outright lies."
],
"score": [
12,
8,
5,
3
],
"text_urls": [
[],
[],
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
ginpjk
|
Why do so many people say older tools (30+ years old) are much better made and higher quality than modern tools?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqfok7q",
"fqfoozf",
"fqgmcvz"
],
"text": [
"Survivorship bias. The 30 year old tools have already held up 30 years while the new tools haven't had a chance to be proven for decades yet. Also kindly forgetting all the tools that broke on them even back then; the ones that are still in the toolbox are a reminder of the ones that survived. You see the same thing about cars, but when you compare all the data old cars were pretty shit and hitting 100k miles without serious work already having been done or even a whole engine rebuild was unheard of. Also a belief that just because something is manufactured outside of (INSERT COUNTRY, typically the US at least within the States) and especially if it is manufactured in China, it is guaranteed to be of inferior quality. Apple has their most iconic flagship product, the iPhone, made in China, and people constantly praise the general quality and durability of them. Simply by working closely with the manufacturer to ensure quality, which any tool company can do if they so chose.",
"I can't comment on the actual quality, but people say is perceptive quality. Older tools were made by craftsmen, for whom the product was the goal. higher quality materials used for high quality product meant loyal customer, repeat customer, and would buy newly invented tools. But, a product which lasts 30 years, means you dont need to buy a new one. case in point, my 1967 fridge, still running. no need for a new one. But modern businesses goal is profit. they want you to buy a new one every 2 years. so they make them to last 2 years on average. cheaper materials used, cheaper to make in poor countries, throw away goods.",
"High end equipment didn't used to be cost engineered. I have several anecdotes. My mom's sixty year old Kitchenaid mixer (now in my brother's hands) and our forty year old Kitchenaid mixer are both capable of kneading nine cups of flour into dough. The same model today will overheat or break, and the customer service line will tell you not to do that. The line has been re-designed to be cheaper to manufacture, and to meet the needs of MOST customers MOST of the time. The blade that came with our thirty year old Cuisinart is still good, despite twenty years of heavy and ten years of light use. We also have a ten year old Cuisinart that's done most of the work for the last ten years. (For a while we lived in two houses. There HAD to be two Cuisinarts. There was much argument about the Kitchenaid). The blade that came with the newer Cuisinart was recently replaced for safety reasons: some time in those twenty years the blade was re-designed to be cheaper to manufacture, without enough concern for impact stresses. Again, it may have been sufficient for MOST customers MOST of the time; ours was beginning to break in the expected fashion. Neither of these were \"planned obsolescence\", nor the poor quality control that low priced Chinese products are currently famous for. The products were engineered by highly skilled professionals to make the companies more money at the cost of quality. On the bright side, Kitchenaid mixers now come in several glorious colors."
],
"score": [
17,
13,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
giofyz
|
How do airplanes fly in tight formation with no roads or lanes?
|
I saw the Blue Angels today. Aside from practice, how do they manage to communicate and fly with such precision?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqftcje",
"fqfsye1",
"fqgfnzj"
],
"text": [
"As much as it seems there would be computers involved assisting them, it’s mostly visual reference and tons of practice.",
"They can see each other. Their motion is relative to each other, not relative to the ground. There is a huge amount of practice involved.",
"The lead aircraft is handling all of the airspeed/altitude/heading for the flight, and he is doing everything as smoothly as possible, nothing abrupt. The lead is not looking at any of the other aircraft. Everyone else is focused on the visual cues of one other aircraft, keeping his aircraft in the proper spatial relationship with it. In the US Navy flight school in Pensacola all the trainees first learn to fly a fixed-wing aircraft, it was the T-34C, a tandem seat aerobatic turboprop when I went through it in the mid-80's. In the T-34 we learned basic aviation, instrument flying, formation flying, and aerobatics. After the T-34 the students go to either helicopters, transport, or jets. I flew helicopters. In learning to fly a helicopter I realized that handling a helicopter is a lot like flying wing (not the lead bird) in a fixed-wing formation flight. It is a process of constant, minuscule corrections. A constant stirring of the controls, pedals, stick, and throttle (collective instead of throttle in a helo). Flying a helicopter or flying tight formation is difficult at first but becomes reflexive after experience. Even though the Blue Angels are flying fast, close and low I doubt that they are breaking a sweat. Edit: To flesh out the way that the wing (not lead) aircraft maintain a perfect position visually: They line up particular visual cues on the aircraft which they are referencing. So perhaps the line of the wingtip to a point at the rear of the cockpit of the lead aircraft is lined up visually, then there will be another visual cue on the same aircraft which also has to be aligned. By using two visual cues, triangulation is achieved and that puts the wing aircraft in a point in space in relation to the lead. Using only one cue, the wing aircraft could be anywhere in a line in space which lines up with the cue. TLDR for the edit: Visual triangulation puts the wing aircraft at a precise point in space."
],
"score": [
16,
6,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
giqw4z
|
When we pay for internet, is that because there is a limited amount of it? Or because it is intangible, couldn’t we all use it for free if companies let us, without any problems?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqg8mj1",
"fqg8yh5",
"fqgf2d5"
],
"text": [
"When you pay for internet you are paying for all the cabel satellites servers etc. That your service provider uses to connect you to the internet. It is expensive to upkeep all of that infrastructure, thous the customer gets charged.",
"think of the internet like the roads and highways. once you setup the infrastructure then you just need to maintain/upgrade it as needed. you might think that using the roads/highways is free, but you pay indirectly through taxes, except for the toll roads. the internet infrastructure is owned by private companies, so you pay them directly for access. since otherwise, they have no other incentive to offer it. once the infrastructure is all laid, it basically costs them the same whether or not there are 1 user or 1 million users. but just like the roads/highways, only a certain amount of people can use it at any given time, or it will be slow.",
"Here’s an economic explanation of it. Businesses primarily operate under two different production functions . Manufactured goods usually have small fixed costs for setting up factories and powering machinery. Every unit they produced costs money in materials and labor. this is where the bulk of the costs come in. In order to make a profit, the manufacturers set the retail price 20-50% higher than what it cost them to produce. Utility companies such as cable and electrical operate differently. Setting up the infrastructure costs millions in upfront cost but after everything is set up, it only costs them pennies per “unit” of electricity or internet used. In order to recoup their investment, the firms will charge a high premium despite the actual cost of sending you the bandwidth is extremely low. In most firms like this, the high upfront costs drives away competition because it is not worth the initial investment in many cases. This is what is known as a natural monopoly, and is the reason internet is so expensive."
],
"score": [
24,
9,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gircua
|
what did Sputnik 1 the first satellite launch into space actually do?
|
I'm just wondering what sputnik's function was was it just a test to show that something could be launched into earth orbit or did it have weather instruments on it or something like that
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqgbsmz",
"fqgrsig"
],
"text": [
"Mostly just showed that it could be launched into orbit. It transmitted radio signals that were used to analyze inonsphere it traveled through. The signal also changed if temperature or pressure was outside certain parameters, so you could say it 'measured' those.",
"It didnt really do anything more than beep. That has a bit of scientific value, since the atmosphere distorts those beeps a little, and therefore you can measure a couple things about the atmosphere, but the psychological impact in america - everyone amateur radio operator could hear that thing - was probably the actual intended effect. Its somewhat logical that the first satellite would have almost no equipment on board: They were in a race to put the first satellite into orbit, and every piece of equipment would have cost time in that race."
],
"score": [
11,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
girm0a
|
So what exactly does 4G/5G mean?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqge9i8"
],
"text": [
"It's the \"generation\" of mobile networks. 1G was just your regular call network. 2G added basic data (text) capability. 3G was when we got mobile browsers and such. 4G just gave us faster data, and 5G is faster yet."
],
"score": [
17
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gisuh3
|
How is Nintendo Switch emulation already so smooth when systems like N64 and Saturn still have issues?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqgnks8",
"fqhau7i",
"fqhi4bp",
"fqhlxz6"
],
"text": [
"The switch uses a pretty well documented SoC (Tegra X1), the operating system is FreeBSD based and borrows some components from Android, and the OS also shares code with the 3dS system software. So there are a lot of knowns to work with. The Saturn and n64, on the other hand, utilized custom chips and black magic.",
"The Nintendo Switch uses a relatively low-power ARM-based processor. Not something too far off to what you would find in a smartphone. ARM is relatively easy for x86 based processors that you'd find in a ordinary PC to emulate (not that it can do it perfectly, but the Switch's hardware is much less powerful then an ordinary gaming PC) Theoretically, the same would go for the Xbox One/One S/One X and PS4/PS4 Pro, infact they should be even easier to \"emulate\" then a Switch when comparing hardware to the same magnitude more powerful then them. Infact emulation may not even be necessary for those consoles. When \"emulators\" for those consoles do come out (as far as I'm aware, there's already a couple, this is just my prediction), they will likely work in a similar way to software such as Wine. This is due to both an average gaming PC and the 2 consoles sharing x86 based CPUs. Those 2 consoles also have AMD GCN based GPUs in them similiar to what you'd find in AMD Gaming PCs The Nintendo 64 and Sega Saturn use special proprietary CPU and GPU architectures that make it hard to be emulated. With little documentation and quite a few differences between these and x86 or a console with a RISC based architecture (such as the Switch, GameCube, XB360, Wii, and WiiU) It is hard to know exactly how to code an emulator that functions correctly or has good performance if you starting at reinventing the wheel.",
"5yo: The switch is similar parts to your computer, so there's less work to do. Older systems were very different from your computer. They had to focus on gaming and were special made for that. So there's a lot more work to convert it",
"The Switch uses a really modern and wildly studied chipset where as older consoles have some really niche proprietary parts."
],
"score": [
97,
22,
15,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gitvp9
|
How do weapons "lock-on" to aircraft and vice versa how do aircraft "know" they are being "locked-on"?
|
I've always taken it for granted in movies and videogames but it just baffles me how long it's been around for.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqgtikz",
"fqgq6fw",
"fqgtvoi"
],
"text": [
"Locking-on is the computer telling the pilot \"hey, there's a thing here I can tell apart from empty air, it doesn't go away and I can keep finding it.\" How it's telling it's doing this depends on how the missile is being guided. Not every guidance system produces a \"lock-on\" warning. For example, Infra-Red Seekers are just cameras that tell a plane apart from the air, because the plane is hotter than the air. You don't have any way to detect this, just like you don't have any way to know if someone is watching your right now on a camera. Radar guided systems on the other hand can be detected. Radars work by shooting out radio waves and reading the bounce. Normally the radar sweeps around a wide area, but not very quickly. The thing just bounce back an you record what direction you were pointing. This is because you just need to know generally where everything is, but don't really need all that much specific. However, if you want a missile with a radar to fly into a plane, you need to be constantly hitting it with radar waves in order to keep up with its exact position. It's alot easier to aim a beam of radar then it is a gun. The plane just constantly bombards the entire area around the target with a lot of radio waves, and it reflects to the missile. Figuring out where that area is, and getting it bounce back would be locking on. But that much radar waves looks very different from just a normal radar scan. The fighters have radio detectors to tell. If it gets hit a lot by radar in a short time span, it sounds the lock on alarm. This is semi-active homing, where the plane is shooting the radar beams, some missiles have their own radar, and they can try to guess where to move their radar scans next. EDIT: Just thought of the perfect analogy for a 5 year old to understand a radar lock on. **You ever watch one of those prison break movies, where they got the search light sweeping back and forth looking for stuff? Locking on would be that light stopping and staying on the escaping prisoner after he got found. Lock on alarm would be that prisoner noticing he's constantly in the light**",
"Homing weapons can work in a variety of ways. Broken down into a few categories we have Active Onboard Guidance, Passive Onboard Guidance, and Offboard Guidance. Shortening to AOG, POG, and OG. AOG shines radar at the target and follows the reflection. If your aircraft is getting blasted with radar that appears to be coming from a moving object or has some other telltale trait, then odds are good that an AOG missile is coming for you. POG uses something like heat-seeking and does not send out signals. This is the hardest to detect, and frankly I've got no idea if or how locks from these are detected. OG uses ground-based systems to track the target and then mark it with a laser pointer or radar 'spotlight'. Such tracking would likely be done with radar and can be detected by listening for the frequent radar chirps that come from tracking radar, similar to AOG.",
"Think of radar like a flashlight. It sends out beams that hit something and reflect back for a \"radar receiver\" to pick up, much the same way a flashlight sends out beams of light than hit something and reflect back for your eyes to see. With this in mind, \"locking on\" to something with radar is like keeping your flashlight trained on a specific person as they move. This kind of \"tracking radar\" for a specific object is distinct from \"search radar\" to simply detect things, in much the same way that turning on the light in a room (helps you see everything) is different than using a flashlight (works in only one direction, but provides a lot of light on a very specific spot) With this in mind, the person being tracked certainly knows there's a light (i.e. \"lock\") on them, because they can see your flashlight pointed at them with the same equipment/eyes they detect the reflections of their own radar/flashlights with."
],
"score": [
10,
6,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
giuamz
|
How do Phones vibrate? What is the mechanism behind it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqguax5",
"fqgs6nm",
"fqh2qm1"
],
"text": [
"There's a tiny motor about the size of a flattened pea that spins a little weight. The weight is off-center so it causes vibrations. Some more expensive phones have a solenoid, which doesn't spin but moves back and forth. These vibrations are more controlled and less noisy.",
"Think of it like a little dumbbell with magnets in it. Imagine a little post going through the handle of the dumbbell so that it can spin around it like a propeller. The phone has little other magnets in it that, when powered, cause the little dumbbell propeller to spin. One of the dumbbell ends is heavier than the other. The shift in momentum from one side to the other extremely rapidly is what produces the vibration.",
"Imagine your washing machine. You know how if you ball up your load incorrectly it starts shaking the machine like crazy? Phones basically do that, except much smaller."
],
"score": [
35,
30,
10
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gix6k3
|
-how can a phone keep things in ram even when it has been restarted?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqh6o6v",
"fqhfu0m",
"fqh74fw"
],
"text": [
"It's not. It has to read it from its non-volatile storage (your flash drive) or, less likely, over the network. Your phone has no non-volatile RAM.",
"I think I know why you asked the question. Did you restart your phone and notice that all your apps were still open/where you left them? That is because the people who make phones realized that being able to pickup where you left off would be a nice feature. In order to do that they save everything(maybe not everything but enough) of the information in the ram about what is open to the normal memory on your phone. When the phone is turned back on it just grabs that stuff and loads it back into ram.",
"Your phone is a specialized and miniaturized computer, like a touchscreen tablet or laptop. It uses the ordinary RAM just like a traditional computer. It has a CMOS which is ROM just like any ordinary computer and it has a hard drive like an ordinary computer. The only difference between your phone and a traditional computer is the size and that the hard drive is solid state."
],
"score": [
7,
7,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gixi1i
|
Why only sunlight can charge solar panels?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqh83f7",
"fqhbeaa",
"fqh8iko"
],
"text": [
"Other light can charge solar cells. However, using the giant free source of light in the sky is the only light source that makes sense for electricity generation.",
"Ok, I have PhD level experience in solar panels. Let me reduce this to ELI5 level. If anything is too complicated or simplified, just reply and ask for less/more detail. So, you know that sunlight can be split into a rainbow? Red, orange, yellow, green, blue, indigo, violet. This is called its \"spectrum\". Sunlight has a spectrum that is brightest in the blue-green part of the rainbow, but has all the other colours too. The spectrum also has some extra colours that you can't see. To the left of red is \"infrared\" and to the right of violet is \"ultraviolet\". You can't see these colours, but you can detect them - IR makes things feel warm (like when you sit in front of a fire) and UV makes things glow, like banknote checkers and disco lights. The left (red) side of the spectrum is low energy, and the right (blue) side is higher energy. That means that to make a \"photon\" (light particle) of blue light, you need more energy than to make a photon of red light. UV is the highest energy and IR is the lowest. When you make a photovoltaic cell (the proper name for a solar panel) you have to decide a special thing called the \"band gap\". This tells you which photons your cell will absorb and turn into electrical energy and which will be wasted. The higher the band gap, the higher voltage you can get with your cell, BUT this means that the lower energy photons don't get absorbed, so they're just wasted. The power you get from a cell is equal to the voltage times the current, and the more photons you absorb, the higher the current. This gives us a problem - you put the band gap low, and you get a low voltage but high current. If you put it high, you get a high voltage but low current. As a result, most cell designers choose a band gap in the middle to get the best of both worlds. Where the best point for the band gap to be is decided by what sort of light you're shining on it. If you were shining only red light on the cell, then making it a high band gap would mean no power at all as none of the low energy red photons would be absorbed. If you were just shining blue light on it, you'd want a pretty high band gap, because you don't want to waste that voltage you could be getting. Solar cells are designed to have the best band gap for sunlight. If you look at a rainbow made from a different light source, you'll see that different parts of it are brightest. Light from an old-fashioned filament bulb is brightest in the red part of the spectrum - different to sunlight, so cells aren't optimised to work with that spectrum. Some LED or fluorescent bulbs have very weird spectra that are more like a series of coloured lines than a rainbow. These have even more problems than a bulb. The last problem is that sunlight is really, really bright. The power of sunlight over a square 1m on each side is 1000W. The most powerful bulb you can usually buy in the shops is 100W. So sunlight is the equivalent of finding the brightest bulb you can find, and shining about ten or twenty of them* on that one metre square, with none of the light going anywhere else. In my job, we have a special light called a \"solar simulator\", which is as bright as the sun. This uses a lot of electrical power and also gets so hot it needs a special fan to cool it down. It makes a little square of light about the size of the circle you can make with your finger and thumb as if you were saying \"okay\". Because the light is less bright (less photons) you get less current. So overall, your photovoltaic cell does work with other light sources, buy you just won't get as much power out of it, and the power might be so low you can't detect it. *This vagueness is due to the spectrum difference - about 97% of the light given off by a bulb is IR, so calculations of how many 100w bulbs are equivalent to sunlight are not trivial.",
"Every light can, but light doesn't have that much energy there is a loss in the process so moonlight or fireflies just won't help. When you are talking about using an electric lamp's energy to create electricity you might want to overthink it one more time by yourself."
],
"score": [
33,
33,
4
],
"text_urls": [
[],
[],
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}
|
[
"url"
] |
[
"url"
] |
|
gixonm
|
how does your phone figure out how full your battery is?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqh9rrl",
"fqhix74",
"fqhno4u"
],
"text": [
"Hi :-) All batteries have a nominal voltage, but the voltage changes depending on how full the battery is (and depending on the load). So your 4.2 volt phone battery will have 4.2V at full charge, and cuts off at 3.3V (as discharging it further will damage the battery). This is not completely linear, but the software accounts for that. Under heavy load (e.g. video, wifi, full brightness) the voltage will drop quicker. Or if the battery's outside and cold. This is the reason why you can sometimes turn your phone back on with a few percent of charge left after it shut off. As for how it's done: There are certain chips and components (e.g. bandgap voltage reference); The simplest is a \"Zener diode\". You can build a very simple circuit to deliver something like 1 Volt as reference Independent from the battery voltage. A microprocessor can than compare the voltage to the battery. If you have a $5 multimeter and like to tinker, you can try :-) Zener diodes are dirt cheap, a few cents a dozen. Or if you are into Arduino/micro-controllers, many micro-controllers have a reference voltage built-in, so you can indeed check your battery status for your DIY projects.",
"Your phone is getting water from the water dispenser. It can see how strong the flow of water is. So it can guess how much water is left in the dispenser.",
"Your phone battery is a bumpin' club in a Saturday night. When you charge it, that's like people going in. You can only charge it so much because there is a maximum capacity. But you also use energy, too, which is like people leaving the club. Phones are complex and always on, so people can come and go at any time in any amount. That's where the bouncer comes in. The bouncer stands by the door and carefully counts everyone going in and coming out. They know the club's max capacity and stop letting people in when they're near it. Because they were counting each individual, they can give you a decently precise estimate of what percentage full the club is at any point. **BONUS** The bouncer NEVER leaves the door. They never actually go in the club. When it finally dies down Monday morning, and they see the lights shut off inside, they can consider whatever that head count is to be \"empty.\" Then when it's at absolute peak time on Saturday, they can watch to see when the people going in can't actually get in, and they update that count to be \"capacity.\" That gets them a really good idea of percentage full at any time."
],
"score": [
84,
17,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
giydgt
|
What's the significance of weight distribution when racing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqhdark"
],
"text": [
"The center of weight in a car is directly related to how it behaves when pushed to the limit. The further forward it is the more understeer you get and the further back it is the more oversteer you get. Having more weight on your drive tyres increases grip during acceleration and having more weight on your steer tyres increases cornering speed. Having the weight high up on the car means it moves more as the suspension is loaded and unloaded."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gizpjh
|
Why is phonecall audio still low quality, despite the fact we can stream much higher quality audio via the internet?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqhlzyo"
],
"text": [
"Because a significant portion of the phone network is still running on the POTS, or Plain Old Telephone System. That is, still the straight up no computers involved wires relays super basic system that's been around since the late 19th century. No doubt any call from a big city nowadays that is any distance, at some point your voice will be turned into bits, and transmitted as data, but for a lot of the phone network, particularly in more remote areas, it'll just be pure wires, and a few basic electronic components more or less. Purely analog. The quality is down to the interaction with those old electronic parts - and it was done like that because it's enough to transmit the spoken word, which is what the phone system was designed to do. Edit to clarify slightly - I'm talking any call that is done as a normal phone call, be it from a cellphone or a landline phone, all of those were designed with interoperability in mind and so they work to the lowest common denominator of quality - i.e the POTS system. With a VOIP based call (Skype, Telegram, Whatsapp, any other online service) those limits no longer apply because for a lot of the calls you're talking across the Internet, everything is just data. So those calls can be much higher quality."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gj1ctl
|
How did we settle on 16:9 as the default aspect ratio for most screens?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqhup71"
],
"text": [
"There used to be a bunch of arbitrary aspect ratio used around the world. 4:3 for TV, 15:9 (European Flat), 1.85:1 (American Flat), 2.2:1 (70mm film). If you overlaid all the old arbitrary ratios, you could put a 16:9 rectangle around them so that all of them could be 100% displayed. But you could also put a smaller 16:9 rectangle inside all of them so that the 16:9 rectangle was completely filled. This means that everything could be adjusted to 16:9 with either a minimal amount of loss overall (cropping to fit), or with a minimal amount of black bars to fill space."
],
"score": [
21
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gj2bei
|
- Why software has to be rewritten or updated for the Apple next gen macbook featuring ARM processor?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqhzl7i",
"fqi06qu",
"fqi0wga"
],
"text": [
"Different processor architectures have different instruction sets. If you think of it as a worker and software as a manual for doing a job a worker that speaks English needs a different manual from a worker that speaks Spanish. Also it's much better to have a native Spanish speaker write your Spanish manual then to have your Spanish workers put the parts of the manual they're currently using through a translator every time they need it.",
"Processors have a language called machine code. Software is written in a human readable programming languages such as C or Python. For such programs to run on a processor they must be translated to machine language. The translation is done by developers when they release their software in a process called compilation. The compiler takes as input source code in a programming language such as C and translates it to machine code. The result is an \"executable\" that can be run directly by the processor. Each processor model has their own machine language, so machine code for one processor model will not work for another. Therefore developers must compile their source code to each of the processor models that will run their program. This also includes the operating system itself.",
"So processors have physical wiring that makes up addition, and multiplication, and branching (if-else conditions), and so many more operations. Each operation has a unique number to identify it, called an op-code, and how each of these operations is actually physically implemented can vary quite drastically, and those consequences have effects on how software runs. So at the very least, source code, which is a text document written by people, that has been transformed into a sequence of binary data, op-codes, an actual program that is fed into the instruction inputs on your CPU, must be recompiled - translated again, so the source code can be mapped to the op-codes of that particular type of processor. Op-code 7 on the Intel processor may be addition of two 8-bit unsigned integers, whereas on the ARM it may be a conditional jump, whereas on the PowerPC they may have reserved op-code 7 and it doesn't even do anything. But more to what I was heavily suggesting earlier, there are definite operational and performance consequences to switching processors. One way to sort data may be very fast on one architecture, but very slow on another. At many levels of software design and implementation, the software architects and engineers have to make decisions that are always a compromise, and either implicitly or explicitly take advantage of the architecture they're targeting. If you're going to sort, for example, there are hundreds of published algorithms to do so, and we'll select one not just based on the data we're sorting, but also the architecture we're sorting on. Programming isn't pure and abstract like philosophy or math, there are real world consequences and we want our software to be correct and run fast."
],
"score": [
6,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
gj3jv5
|
How does the OnePlus camera see through plastic?
|
URL_0
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fqi8s9y"
],
"text": [
"It sees infrared, and that box is made of infrared transparent plastic, which is probably used because that device has a remote control that goes with it."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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