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he4vzm
|
How are movies filmed in busy cities like New York City and San Francisco?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"About 10 years ago I saw them filming Transformers in Chicago. Pretty much they shut down the street and all the cars and things that you see in the movie were brought in. It was pretty cool.",
"the producer contacts the city and secures a filming permit that allows them to shut down certain areas during certain times. for money. [ URL_0 ]( URL_0 )"
],
"score": [
14,
7
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"text_urls": [
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[
"https://www.youtube.com/watch?v=3t4X3mBYWEw"
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|
[
"url"
] |
[
"url"
] |
|
he730o
|
Why does a laptop gets slower
|
I used to play a wonderful 5 vs 5 team fight in dota 2 when i bought this laptop, but now, 5 months later, the image gets slower during team fight, Can someone explain me why does this happen?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvpjbqq",
"fvpi0le",
"fvpoki7",
"fvprpsc"
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"text": [
"A common problem with most people who are not, IT saavy, is they install anything and everything, that looks interesting. The general rule of thumb here is, (without getting too technical), the more shit you install, the slower you computer becomes....",
"Virus, out of date software and wear and tear Your pc shouldn't be slowing down after 5 months it takes at least a year or 2 to see the difference.",
"Just want to add, check the vents for stuff blocking the fans. A clogged vent could drastically affect performance",
"Over time as you add more and more software to a computer you end up with increasing background services. If you ever encountered the term 'daemon' then this is an example of such. Bootstrap is another term associated with these. These are (usually) small pieces of code that run at startup, often launchers for larger applications. (Steam is a good example, it might not fully open on startup, but it's daemon does. Antivirus software is another common example) You can view these on Windows OS via ctrl-alt-delete and the right-most tab labelled 'services'. It is worth noting that a range of malware and assorted junk software commonly add such startup processes. Additionally if you buy a machine with preinstalled OS then there may be a variety of software installed that you ultimately do not need yet clutters this list. So as the number of these background services increases, the 'idle' load on your CPU and memory increases, leading to lowered resources and therefore performance. Be wary purging background services via the above mentioned list, the operating system itself adds a number which are more or less needed. You want to positively identify anything before ending it. It is good practice to occasionally do a clean reinstall of your operating system. Either from scratch or from an image created shortly after such an install. Edit: this became less ELI5 and more Eli adult but not tech-savvy. I'll leave it as such, is hard to avoid with IT"
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8,
7,
5
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|
[
"url"
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[
"url"
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he8vhx
|
Why does the device itself need to have a restart after downloading an update for a program?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvpwhhq"
],
"text": [
"When a restart is needed, it's usually because one or more of the files that downloaded were already being used and can't be updated while it's loaded in memory. ELI5... You need new tires for your car, you have to stop the car to put new ones on, you can't upgrade them while they're in use."
],
"score": [
21
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
he9cpm
|
Why erasers work well with normal pencils but not so much with colored pencils?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvpw5u8",
"fvpvso0"
],
"text": [
"“Normal” pencils tend to have a nib made of graphite, which actually kind of peels in layers. When you write something in graphite, you’re depositing a superficial “layer” of graphite on the paper. The eraser just rubs off the top layer of the graphite. Many coloured pencils contain wax or other like substances that permeate the surface of the paper and thus are harder, but not imposible to rub off. Tl;dr: “normal” pencils only affect the surface of the paper, coloured pencils seep in deeper. The eraser is more effective on the surface.",
"Colored pencils are wax (correct me if I’m wrong) so erasers meant for graphite won’t really be too effective on them"
],
"score": [
18,
5
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
heb9mr
|
what is a driver for example a compiler driver
|
what is a driver?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvq96if"
],
"text": [
"It's a layer between HW and SW. Hardware is controlled by writing ones and zeros into its registers at different addresses. For eaxample you want your printer to do some task, like go to standby mode so you write 10101111000011010 into address 0x5f4c (I made these numbers up....). But every device has thousands of these instructions and address cells. Driver's job is so the programmer doesn't have to remember all these instructions but instead they use something like printer.goToStandBy() and the driver translates it to ones and zeros that the printer understands"
],
"score": [
5
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
hebe3q
|
why do moving parts in video games are usually a different color than still objects ? (e.g. a drawer that is supposed to be opened is a lighter color than the other ones)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvq8be2",
"fvq73zt"
],
"text": [
"Depends on a few factors. In modern games, this is often a design choice to make something catch your eye. In the older (DOS-era) games this was often a by-product of still backgrounds versus movable sprites or objects, where it simply was really hard to colour-match the two.",
"It's a deliberate design choice so you notice it and try interacting with it. Otherwise it would often be too hard to find out what _can_ be interacted with and players would get stuck and get frustrated (Often the direct result of beta testing, because changing the color isi usually really easy to do without the risk of creating additional bugs)."
],
"score": [
9,
9
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hecy77
|
what the hell is "Randonauting" and how does it actually work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvqj4di"
],
"text": [
"Randonauting is telling your phone, \"I don't want to go any further than\" and you tell it a distance. Then your phone tells you a random place within that distance from where you are, and you go to that place and see what is there. [ URL_1 .]( URL_0 .)"
],
"score": [
3
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"text_urls": [
[
"https://www.wired.co.uk/article/randonautica-lockdown#:~:text=Randonauting%20is%20using%20a%20random,exploring%20the%20world%20around%20you",
"https://www.wired.co.uk/article/randonautica-lockdown#:\\~:text=Randonauting%20is%20using%20a%20random,exploring%20the%20world%20around%20you"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hedo9a
|
How do video game companies improve their graphics? What makes game engines better than others?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvqlose"
],
"text": [
"Graphics are a complex combination of resolution, lighting, artstyle, shadows etc. To create an object in a game you have a texture which basically is the \"skin\" of the object. This texture is basically a painting which can look like 3D even though it is 2D. This can make a flat wall look like a stone wall with cracks and crevices. The resolution of this texture is decided by how many polygons you have. A polygon is basically a small coloured area and the more you have, the more realistic your texture can become. But more polygons takes more processing power to render, so you need a more powerful graphics card. So one way of improving graphics is to have a more powerful card and add more polygons. For shadows and lighting you have algorithms that can calculate light reflections on surfaces, how a light source interacts with the surrounding etc. These algorithms are being improved over time and help create more realistic looking games. He art style can also have a big impact. Some games look very realistic while others focus on a more cartoon style. Both games can still have very high resolutions and fancy lighting, but they give very different impressions. Game engines are basically what brings it all together. The game engines also play a huge part in the physics of the game. Game engines are improved and optimised over and it's not uncommon for game developers to develop a new game engine to allow them to run the game the way they want. With game engines a lot depends on the coding and how it interprets and renders everything. A powerful but poorly optimised game engine can struggle to run a game while a less powerful but well optimised can run it smoothly."
],
"score": [
8
],
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|
[
"url"
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[
"url"
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|
hedrqo
|
how do particle accelerators work?
|
I vaguely get that they use magnetic fields to zoom particles along like rail guns use magnetic fields to zoom bullets along. But what I don’t understand is how magnets can move particles that aren’t magnetic. And how do you aim two microscopically small particles that are zooming near light speed at each other?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvqkkzm",
"fvsl33b"
],
"text": [
"You are right: they use magnets. And you are also right that they cannot move particles with no charge. Electrons and protons have negative and positive charges, respectively, so they can be zoomed along, but neutrons, no charge, no move. If you want to smash things into neutrons you just make the neutrons a stationary target. Or you can use ~~Beta~~ alpha particles, which consist of two protons and two neutrons (and yes, that's a helium nucleus) so the protons have a charge and the particle can be zoomed. As far as making the particles hit each other, they don't just zoom one particle and try to hit another single particle. They zoom a whole stream of particles and then spray the stream at the target, or spray two streams at each other, and watch for collisions. How they see the smashes is another whole deal, but you didn't ask about that! 8p",
"There's a lot of repeating *bad* answers here. Particle accelerators do *not* use magnetic fields to increase the speed (energy) of particles. They use electric fields. Tldr: particles in an accelerator are like cars on an oval race track. The magnets are like the steeply banked ends that turn the car without speeding it up. The cars speed up in the straightaway (due to powerful electric fields). Particle accelerators only work with electrically charged particles. Typically, they start with a particle that may or may not be electrically charged (like maybe an atom). The particle is made to be charged by adding or removing electrons. The particle is injected into the accelerator typically by having a large voltage (like 100,000 volts) between the source of the particles and the start of the accelerator, with the polarity of the voltage set to push the particle into the accelerator. In the accelerator machine, there are regions that have large magnetic fields and regions that have large electric fields. The magnetic regions are used to turn the particles and also to focus the particles into a nice narrow beam. They don't speed up the particles. They only change direction. The electric regions \"boost\" the particles to a higher speed. One common design approach uses electric fields that rapidly switch, so that the particle gets pulled toward a place and then once it gets to the center, the field switches so the particles are then pushed forward. Like pumping your legs on a swing. The magnetic fields are just like the banked corners on a racetrack. They don't make the race car go faster, they just turn it. The timing of switching the polarity of the electric fields controls the speeding up of the particles. Eventually, though, they get so fast that the magnetic fields can only barely turn them enough to stay on track. That sets the maximum speed (energy)"
],
"score": [
25,
3
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
heegaj
|
Why are sites 'down' during maintenance? What prevents changes to be made while users are on the site?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvqq4ax",
"fvr559p",
"fvqogc1"
],
"text": [
"By putting the site into a maintenance downtime, you prevent any weird scenarios where users are trying to use the site and possibly create corrupt data because they fill out a form on the old version of the site, but it gets submitted to the new version of the site. The specific errors that could happen are of course going to be unique from one webapp to the next. You could also code your website in such a way that everything goes seamless, but that is a significant cost.",
"It's the same reason you can't browse the internet on your computer while it's rebooting. \"Maintenance\" has some similarities to installing updates on your computer. In fact sometimes \"maintenance\" is *literally* exactly that: the servers that run a website need OS upgrades for security reasons. So they install the updates and reboot the servers, and the site is down while the servers are rebooting. Avoiding maintenance requires extra cost. Either more servers, or more complicated software in one way or another. Even just having multiple servers and rebooting one at a time has complication: Your servers are running two different versions of software! Can that cause synchronization issues? Turning everything off while you're upgrading is the *simplest* solution. Whether it's the *best* solution or whether it's even *feasible* depends on the specific site and a whole host of business considerations. There's more tools for it nowadays than there used to be, but it's still not trivial.",
"Because you can't edit something that's actively being used. Imagine trying to renovate a restaurant, you wouldn't leave it open and let customers have a poor quality experience. It would be entirely possible to leave the site up, but with maintenance happening it makes sense to stop access to the site during the period you know there will be service disruptions. The site admin will usually take priority over anybody else trying to use the site, so it would disrupt their enjoyment of the site if pages never load and comments never get posted."
],
"score": [
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5,
3
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[
"url"
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[
"url"
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|
hefil5
|
phones that take sd cards, why is there a limit on how big a card they can take, why cant it be the biggest available
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvqwhm2"
],
"text": [
"Because there are different standards of information for encoding on larger SD cards. This is because larger SD cards required entirely new technologies in order to be able to create. This means that larger SD cards effectively write and speak in a different language, so a phone has to have some way of adapting to that in order to use them. Many phones can be patched to do this, but really old phones might not even have that ability."
],
"score": [
14
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hegloj
|
What is permaculture, and why is it more sustainable than traditional agriculture?
|
I would like to know more about permaculture and how it works. If someone could explain, that would be great! I saw a visual about it on Instagram and now I’m curious.
|
Technology
|
explainlikeimfive
|
{
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],
"text": [
"Modern Agriculture is taking large steps to help revive the soil, but overall, permaculture is usually done in very small cases, and is too expensive and needs too much care to be used in large scale agriculture. There is a brilliant podcast, \"Field Work\" that is co-hosted by a youtuber who goes by the name \"Millennial Farmer\". It is completely based on making Modern Agriculture more sustainable. [Millennial Farmer's Channel]( URL_0 ) [Field Work Podcast, Youtube]( URL_1 )",
"My understanding is that permaculture is centered around rejuvenating the soil. traditional agriculture strips the soil of nutrients and often does not replace them. It is centered around low costs and high yields. Permaculture is designed to be better for the soil at the cost of efficiency",
"Many have explained it well already, but wanted to give an example of a natural form of permaculture. When you look at a forest, everything is working to support everything else. even the critters that eat the leaves, will benefit that plant in one way or another. this forest can be around for millennia, nobody needs to pull weeds, plant seeds. or add fertilizer. permaculture, in many ways tries to mimic these natural systems, but at the same time produce resources for us humans ( and other animals ).",
"Permaculture takes inspiration in natural environments and on utilising them in the most sustainable way. I'll give you an example if you are planning a garden but you live in the desert then a 'perma-garden' would take into consideration that water is a rare resource and that temperatures are high so growing massive grassy lawns will most likely not succeed unless massive resources are wasted per square metre or foot if you prefer. So planting local growing plants, trees and bushes are part of permaculture. But it goes further than that as well, it looks at mimicking natural environments in a way that are utilised for agriculture as well, such as choosing and rotating your crops in such a way that the soil is naturally replenished by the crops, requiring less or no fertilisers, and using insects and birds as natural pesticides. Basically creating gardens and agriculture that integrate with their natural environments."
],
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4,
3,
3
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"https://www.youtube.com/channel/UCp0rRUsMDlJ1meYAQ6_37Dw",
"https://www.youtube.com/channel/UCbU2Nyq0vQlPUCxlTcGFo0w"
],
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|
[
"url"
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[
"url"
] |
hek4f1
|
Why was art from the Middle Ages so different?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvrpx5k"
],
"text": [
"So as the Roman Empire fell, and most places were conquered or left in chaos, a lot of the artistic developments of Greece and Rome faded away. 1 point perspective, 3 point perspective, and so on would be lost for a long time. But not only that, at the time most couldn't read, so artists needed to make religious works easy to follow, with defined symbols and elements that would be recognized by any person. (Think like, how Batman wears a cowl with pointed ears, anyone would know thats batman, even if it wasn't 100% accurate. This would apply to religious leaders, with stuff like the color of their garments donating their position) Most artwork of medeival europe were done by Monks, and they often would create hundreds of characters with the same generic face to differentiate the commom folks from the important ones, who were the only ones whos images were made in their likness."
],
"score": [
12
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
heln1w
|
How does data transmission from something like the ISS work? Those are massive distances and i guess a whole lot of data. Are there some special protocols are massive antennas?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvrzo10",
"fvs0beg"
],
"text": [
"The ISS is **much closer** to your house than the DirecTV satellite that sends your TV programs. Not at all a massive distance, it's 400km (about 240 miles) above the surface of the Earth. There are some nice antennas and a network of ground stations, but it's nothing like New Horizons photos from Pluto.",
"The ISS is actually confusingly close often times The ISS orbits just 400 km above Earth's surface while Geostationary communication satellites like those that provide Satellite TV and Internet hang out at 35,000 km above the surface Communication with the ISS is done through communication with satellites in geostationary orbit(TDRS) and large antennas on the ground(Space Network) and works pretty similar to standard satellite internet. They got an upgrade recently which brought them from around 10 Mbps to 600 Mbps"
],
"score": [
11,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hely6y
|
How do multiplayer games sync player actions with each other?
|
I know some of it has to do with the server side of things but at some point you have to lend some things on the client side, correct? I'm curious on what typical multiplayer games do server-side and client-side and make sure that everybody sees (mostly) the same thing while accounting for lag and all that. Not necessary but I would also appreciate knowing how peer-to-peer vs. dedicated server environments tackle these issues as well.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvs40o3"
],
"text": [
"Dedicated server: The basic run down is that your client shares information with the central server who then distributes the information to everyone else's clients (and gives you their data). Since all of this exchange is handled by the server, your client (and device) just has to handle decoding the incoming data and sending your new data to the server. To ensure players \"see\" the same thing, time stamps and packet numbering is used in addition to some predictive measures on the client side (sometimes not always). The server tries to balance all the lag/latency by sending the smallest packet of information possible; all the participants' clients will try to do the same. Other latency/lag balancing measures is sending only information that is needed to the clients that need it. EXAMPLE: In Minecraft, only locations with active players need data to be sent to those players. So the player(s) in chunk (136, 250) get sent the data of that chunk and the chunks around it up to the render distance (typically between 8 and 16 chunks.) Any changes made in these chunks are sent back to the server who then sends the updated data back to the players; these packets are quite small as ONLY the changes in blocks (which is about 3 bytes in size per block) and player locations are sent (these changes can be larger in size than block data as they tend to be vectors of about 8 bytes in size, but also the server uses some predictive measures to ~~guess~~ calculate what a player's new location will be.) Peer-to-peer: Pretty much the same, but instead of sending to a central server that then sends out to everyone, your client (and device) send the data directly to everyone else's client. This method does not have a great way of handling lag/latency as packet numbering can vary between peers. Also since your device's internet connection is now having to handle multiple connections to other players, instead of just one connection to the server, it can run into bandwidth issues. The same smallest data packet principal applies here as well."
],
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23
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|
[
"url"
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[
"url"
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hemp0t
|
If aliens were trying to communicate with us would we even notice?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvs6bg8"
],
"text": [
"We don’t really know. They could communicate to us through things that we understand like radio and light, or they might not and use things that we haven’t even discovered yet. It all depends on how advanced the aliens are"
],
"score": [
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hentgc
|
4K 60 fps games are so smooth , but we don’t see things like that when we look around in real life. How can something artificial look smoother than it’d be in real life?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvsdoqg",
"fvsea7i",
"fvsez9k"
],
"text": [
"Reality is much, much more complicated. It would be super smooth, if everything were smooth and uniformly lit. But, almost everything in reality has 3D texture, and there is this super bright unshielded nuclear reactor in the sky every day making super harsh shadows.",
"I believe it is because the actions are not smooth in real life. In a simulated environment like a video game every move of an object is equal, or defined by smooth relations. In real life every move is a little different than the previous and it doesn't appear smooth to us. When you take a step in an fps game it is always one meter per step on real life one step is 1 meter the other one is 1.05 meters Think about the difference between a good dancer and a bad dancer. A bad dancer will look clunky to you but it is not due to your inability to see smooth dance moves. A good dancer on the other hand is impressive because it is actually hard to control your movements on such a degree to make them smooth",
"It actually might be the motion blur on your TV or in the games, or it also might be how you're used to sub-60fps games especially if you're used to playing on console, personally I've recently upgraded from 60fps/Hz monitor to 144hz one and tried playing games that can reach 144fps on my PC, I did experienced the same thing, eventually it feels natural and \"not smooth anymore\" to me but when I look back at 60fps stuff I instantly notice the choppiness."
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5,
4
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"text_urls": [
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|
[
"url"
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[
"url"
] |
|
hepbhh
|
What exactly is "hacking"? How do people even learn the basics or get into it in the first place?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvsounw"
],
"text": [
"First you need to understand how everything works. Networking, computers in general. You need to be good in some programming languages. There are many ways to do it. 1. The easiest one is you using a keylogger which is a program that \"listens\" to your keypresses. Then you open a file that program has stored keypresses to and just read it manually and voila. 2. It is by being \"the man in the middle\". Listen to communication between the victim and others. 3. By making victim accept a malware that is doing some thing in the background. For example you send a verification mail from 'instagram'. You make a temporary site and make it look like a real instagram notification. Most people are not picky to see every detail they get in the mail. By putting their password direct to that verification you get it.[example]( URL_0 ) This is more social but you get the point. 4. Social engineering. This is the 90%. The weakest part in ANY system are humans. For example you make the support service think you are wife or husband of the victim and thar you lost the password and there are important things but he isn't there atm and he/she needs it NOW. [example]( URL_1 ) You need to understand a particular thing how it works in order to find holes in it. Tldr: Usually you attack human's naiveness. Or make them give you unknowingly by accepting \"verification\" for xy and re-entering their password, ie. Giving you directly."
],
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3
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"https://youtu.be/PWVN3Rq4gzw",
"https://youtu.be/lc7scxvKQOo"
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|
[
"url"
] |
[
"url"
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|
heu3yv
|
How is mail sorted?
|
So I had a thought when I mailed something the other day - how does mail get sorted? It’s honestly amazing that mail travels as fast as it does once I thought about it. But that starts with your local post office sorting it - so obviously it’s not done by hand, but how does a machine read people’s crappy handwriting? Or is it done some other way?
|
Technology
|
explainlikeimfive
|
{
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],
"text": [
"If we are talking about the USPS then here’s how I understand it. A computer sorts almost all of the mail. It takes a picture of each letter and uses handwriting recognition software to compare what it thinks the address is to a list of known addresses. If it finds a match, it prints a barcode on that letter that make it easier. You’ve probably seen this weird barcode of short and tall lines at the bottom of envelopes mailed to you. From there, robotic systems take over sorting and moving the mail around the sorting center. This is how 98% of the mail is sorted. For those 2% that have illegible addresses (either damaged or bad handwriting) the machine sends a picture of the envelope to a person at a computer, who tries to work out what the intended address is. Most of the time a human can figure it out. When the human can’t figure it out, it goes to a lost mail center, where other people take much more time to figure out where the letter goes. They may be able to figure it out on a partial address, or a name and a city or something like that. Now if the letter had a legible return address, it would likely be returned to the sender before being sent to the lost mail center.",
"Have you seen Man in Black 2? (Sorry, I had to....)"
],
"score": [
18,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
heuiy7
|
How do music leaks happen? Who is holding the music before the release and how does it get out?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvtmizq"
],
"text": [
"Publishers send out several waves of advance copies of the songs on new albums before the album comes out. The first wave goes to people in the industry. As songs are completed they get sent to a bunch of other artists and producers who are making the same kind of music. This is both to make sure the song is good and to also make sure it isn't a case of unintentional copyright infringement. Its not unheard of for artists to unknowingly copy portions of other songs that they've heard and sending out advance copies gives them a chance to fix issues like that. Also sometimes the songs just suck and end up getting pulled. The second wave goes out to radio stations. Once most of the songs have been finalized the best songs are sent to radio stations a few months before the actual album comes out so that the radio stations can build hype for the album. Once the full album is finalized the final wave goes out to executives that work for major music retailers. The idea is to convince those executives that the album is going to be a good seller so that they'll give it better/more shelf space. What this means is that thousands of people are getting advance copies of songs from the album, and possible even an advance copy of the full album itself long before it comes out. Any of those people can easily leak it. If they get caught then its a huge problem for them but the chances of getting caught are pretty remote."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
heuu64
|
If apps don’t read my password, how do they decipher if it’s a strong or weak password?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvtoice"
],
"text": [
"During password creation, apps accept the plain text password and evaluate it for complexity. If it is not complex enough or does not meet other defined requirements such as minimum length, the app notifies the user. Checks like this usually happen before form submission but sometimes after as well. Applications most definitely read passwords at certain points, like during password creation or authentication. Many applications only broker a connection between the user and an identity provider such as Facebook, and truly do not store or read the password ever, as the identity provider credentials for the user are used. Additionally, many apps use an identity and access management platform to manage their users, so they simply pass usernames and passwords to these platforms that specialize in handling authentication and storing information such as passwords in a secure way."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hf24ej
|
Why do condenser microphones need an external power supply? is there a way for them to work without power supplies?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvuthlm"
],
"text": [
"Batteries. The power required to operate a condenser circuit is 50 times more than the sort of mic your computer might be able to power. Since applying condenser voltages to such a low-power mic would fry them, you computer designer's not going to want do that."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hf5red
|
Backfeeding
|
Currently the guy who installs all the internet stuff is here at my house. He just told me that if I wanted to I could “backfeed and get connection in all the rooms.” I have no idea what he’s talking about and he keeps calling me young lady so I feel weird and I’m too afraid to ask. I tried to google it but understood absolutely nothing of what I read. TIA
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvvi15s"
],
"text": [
"\"Backfeeding\" is basically a reversal of the normal flow of electricity or another signal through a system. For an analogy imagine you have a plumbing system where water comes in from the mains and is distributed through various pipes to faucets and spigots for use. \"Backfeeding\" in that case would be like attaching a water source to one of the spigots and pumping water into your plumbing system, \"feeding\" the plumbing system backwards from normal. What is being talked about here is using the telephone wiring in your house to distribute an internet signal from their modem. Normally there is a central connection which links the wiring within your house to the telephone system at large. If you disconnect that link then you have an isolated set of wires going to every room of your house, and then you can plug their modem into a nearby telephone outlet. Their modem acts differently than normal, providing its own dial tone to the wiring as if it were coming from that central connection. Because it is linked to the wiring through a normal outlet it is considered \"backfeeding\"."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hf6e1m
|
How come in some photos of the sun/moon they look enormous, when in most photos they show up as tiny dots in the sky?
|
It seems like it's usually in professional photos that they look huge - sometimes bigger than they look to the human eye. Is this photo editing, or the type of camera, or what?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvvwtpg",
"fvvrwpu"
],
"text": [
"Please don't bother about the answers with Photoshop and horizon effect. Enormous moon and normal sized trees is down to a trickery of lens on telephoto lens. I quote from stackexchange: \"Those are done using the compression of a telephoto lens. Longer lenses will magnify the subject, so will make the moon look bigger. It will also make buildings and other objects bigger, but by moving yourself further away from those earthbound objects you can reduce them back to a smaller size. But you can't really get further away from the moon, so it will remain the same size no matter where you move locally. The shot might look like it was taken from a short distance away with a 50mm lens, but in fact it may have been taken much further away with a 500mm lens. Result is the foreground looks about the same as if you'd taken it closer with a 50mm lens, but the moon on the other hand is magnified quite a bit.\" Here's a stunning display of this effect with sun. URL_0 And the best display and explanation of this phenomenon is in the following Wikipedia article. URL_1 Look at the caption under the pictures of blue and pink bottles. It says, \"How focal length affects photograph composition. Three images depict the same two objects, kept in the same positions. By changing focal length and adjusting the camera's distance from the pink bottle, it remains the same size in the image, while the blue bottle's size appears to dramatically change. Also note that at small focal lengths, more of the scene is included.\" In this example, the blue bottle is the moon and the pink bottle is trees and buildings.",
"Also the moon looks way bigger next to the horizon. I’ve gotten some pictures where even though the moon is “low res” (because I took the picture with my phone) I zoomed in and got a picture of it right next to the horizon, so it looks big. If you think of the moon rising above a church that’s on the horizon, then imagine that you zoomed in so far that only the church and the moon were in the photo, it’ll look gigantic!"
],
"score": [
5,
4
],
"text_urls": [
[
"https://www.dailymail.co.uk/news/article-2167595/Stunning-image-shows-boy-watching-solar-eclipse--taken-1-5-miles-away.html",
"https://en.m.wikipedia.org/wiki/Wide-angle_lens"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hf7br8
|
Is dehumidifier condensate safe for drinking?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvvqwl3",
"fvvrcyy"
],
"text": [
"It’s technically distilled water, which is safe to drink in reasonable amounts. In large quantities it can cause some issues since it’s extremely low in minerals and will start drawing them from your body. It’s not necessarily clean though, depending on how well you’ve been maintaining your dehumidifier.",
"The vast majority of dehumidifiers have mold somewhere in them so I don't know if I'd go drinking that water. Plus the other poster is correct, there is no nutritional benefit to that water it in the long run it will actually steal the element and minerals your body needs to function. I guess if you're in a hurricane and you haven't had water for 5 days and things are starting to get blurry and your temperature is 102 then maybe."
],
"score": [
15,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hf9stk
|
Why/how do computer screens in movies not have the weird rainbow effect on them (the moire effect)?
|
I already know why that happens when you record something on your phone- camera sensors aligning and misaligning with pixels. But how do they get rid of that effect in movies/tv shows?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvw8h8k",
"fvwayhb",
"fvwdpaa"
],
"text": [
"I may be way off base, but I believe in tv/movies, images on computer screens are typically digitally inserted and not actually recorded.",
"In addition to the other answers, the moire effect is reduced to unnoticeable levels if the screen is not in sharp focus or at certain angles.",
"Some brief credentialing for where I get my info: 10 years ago I got my bachelor's degree in Animation, which included courses in video editing, composition, and special effects. Made some student films, grappled with a lot of that stuff, but in the end I worked in IT. I own my own copy of the Adobe suite, the pertinent tools to this topic being AfterEffects and Premiere (their special effects and video editing tools respectively), and I do video editing on occasion for freelance work since it was the most enjoyable aspect of that for me. That said: I've never worked on anything big budget, and the research I did into this is at least 10 years old, so there may be different standards now. That said, onto the answer: Sometimes they will try to match the camera's sensors to the image's pixels, take the shot from a perfectly straight-on angle, and just know both the TV and the camera well enough to frame the shot that way. More often, though, they'll take a still-shot of the scene without actors with the monitor off, then shoot the scene with the screen in it, then capture (or just animate and render) the video of what should be happening on screen, and then use special effects to put the animation or video of what should be on the screen... well... on the screen. If the scene is relatively stationary, they may just manually cut out the area of the screen from the shot and put the video on it, ~~but if it's a moving shot, more likely they wrap the TV in greenscreen material so that it can be chroma keyed out (a quicker ELI5 for anyone who is confused by that term, \"chroma key\" is the term for the effect that most people know as green screening: editing something out of a piece of video based on its color. Green is the most common [though as a kid I remember bluescreens being discussed in this context, I don't know why they changed offhand], but the software supports the use of any color as the \"key\" color to remove from the video)~~ This was a kludge by me, not industry practice, hence my disclaimer; see replies :)"
],
"score": [
44,
14,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hffmit
|
How were programming languages invented?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvxc0os",
"fvxezug",
"fvxfxw6",
"fvxdu0a"
],
"text": [
"They were painstakingly written in binary code first, to write assembly language. Assembly is human-readable code that gives the computer instructions in binary. Once assembly was written, it was used to begin writing more complex languages. It just grew from there.",
"The history is pretty interesting. The main ideas of computation were developed from mathematics and logic. It is probably fair to say that a lot of this was formalized in the early 20th century. The symbols and methods predate electronic computers. Computation involves solving some mathematical problems by following a certain procedure (algorithm). This procedure can be performed manually, mechanically or electrically and the device or people doing it were called computers. The first high level programming languages were essentially formalizing these mathematical ideas along with some ideas of a device (mechanical/electrical) to perform computation. These languages were sometimes more theoretical and it took some time before the actual computing devices could implement them. Fortran is probably one of the oldest programming languages used in \"modern\" computing. It is a fairly simple language with small instruction set. It was written mostly to perform arithmetic calculations. The name itself comes from \"FORmula TRANslation\". As electronic computers developed, more languages were developed some for specific purposes like COBOL (business oriented computing). So, in an odd way to the modern person, one could say that the math and science of programming languages contributed to the creation of the computer and not the other way around.",
"You can invent one right now too if you knew what to do, but sadly it's at least a couple of full semester courses, so I don't think anyone can summarise it into one comment here Some people mentioned that they are written in binary, but that's thankfully not what we do at all. They are written in already existing languages like c, and tools like lex and yacc simplify this a lot. The original languages were written in assembly code. (Assembly code is basically the closest you can get to binary code while still typing English words. It relies on the principle that you can load and store instructions just the same as data in a computer's memory, and doesn't deal with variables but rather registers and immediate memory locations. For example, if you have 4 bytes per instruction, the first 4 bits can specify the format for the rest of it, and one of those formats can have the next 6 bits specifying the instruction, the next bit can be a flag telling whether you're going to specify a register or a memory location for the input, the next bit can be a flag for whether it's a jump statement, the next 16 bits could be pointing the a location in the memory to read from, or directly a numeric value, the next 4 bits could be the name of the register to store the output into, etc. But you just write ADD R1, R2, R3.) So if you want to create a programming language, there's multiple phases. The first and the only one where you're \"inventing\" the language is the design of its formal grammar. You are basically going to write what would be syntetically correct in your language, and what would it semantically mean. A grammar is a collection of statements like [S - > A B] where A could then be [A - > A1 B1] and so on, or [A - > t] where t is some terminal symbol. You can be as creative as you like here, but the important part is that there should be no ambiguities. An example would be, in C, + means addition and ++ means incrementing an operand. Now imagine c allowed you to use social characters in variable names; if I said i++; i chould be saying \"increment the variable i\", \"ADD the variable i to the variable +\", or just mentioning a variable named i++. Since the compiler won't know which one you mean, that's an ambiguity. It would take months to learn how to detect and remove ambiguities in your grammar so I won't go into more detail. Now once you have a grammar, you should write a program that takes in a text file written in your language, and line by line translates it to an equivalent line in another language. Either assembly code itself, or into some other language whose compiler you have which you can then use to convert that into assembly code. For this, it is simple to use lex and yacc. In lex, you define what all characters and keywords are valid in your language and pass tokens from it to the yacc program. The yacc program holds your grammar and matches each line of tokens it gets to fit some line in your grammar. If it gets a fit, it executes whatever c code you have written for it to be equivalent to that line. If it doesn't, it gives an error. I have grossly oversimplified many things (and may have been a bit inaccurate on others) but that's the general gist of it. Someone who knows better can correct me if need be.",
"Programming languages, are basically shortcuts for people to write binary. So lets say that in the olden days you had a string that said \"01001000 01100101 01101100 01101100 01101111\" This is just the word \"hello\" in binary, now we dont want to press all these zeroes and ones to write a word so we told the computers that whenever we touch the \"h\" button we actually mean 01001000. This is what programming languages do aswell but then on a much more complicated level, with logic circuits and such. P.s. not a programmer myself, this is how it was explained to me by a friend who is one."
],
"score": [
19,
11,
5,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfgnc8
|
How does the cremation process actually work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvxh5ce",
"fvyin6a"
],
"text": [
"Basically a body is put in a cheap easily burned container, a cardboard or thin wood casket, it's then burned at an extremely high temperatures in a gas furnace, called a 'retort' until all moisture has been removed, all tissues have been reduced to just some carbon ash and trace minerals, and the bones are reduced to extremely brittle chunks of dry calcium. It's the bones that form the majority of the 'ashes'. After burning, the cremains are tumbled with steel balls or processed through a bladed grinder (known as a Cremulator) to produce a powder that resembles fine gravel. So in realty, the majority of cremation 'ashes' are actually just incinerated powdered bones.",
"There’s also the increasingly popular water cremation. The body is put into a vat of liquid until it dissolves, then the mineral content is filtered/extracted. It sounds gruesome, but it’s far more environmentally sound than heating an oven with fossil fuels."
],
"score": [
45,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfiwve
|
Why does the Spotify radio algorithm always suggest horrible songs for my playlist, even when there are great, well-themed songs out there I haven’t heard of?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvxshx5"
],
"text": [
"Your friend and you make different \"thumbs up/thumbs down\" choices when presented with songs. Spotify uses these choices to offer you new songs, based in part on what others who have made similar choices have found favorable. So if you say UP to Song A and DOWN to Song B, Spotify looks at users who have done the same (UP for A, DOWN for B) and finds a song that most of them gave a thumbs up to (Song C) and presents that to you. And the process continues. For whatever reason, you've made different choices when presented with certain songs than your friend, so you don't get offered the same songs. Spotify uses the exact same algorithm and process for you and your friend, so the different song lists are the result of the different choices you've made. Have your friend curate your Spotify for a few days if you want to be closer to your friend's playlist."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfruf9
|
Why is adobe flash player ending?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvzeild"
],
"text": [
"Flash, from the get-go, has been riddled with security holes and flaws, and is generally resource-hungry and unwieldy. Ultimately it makes more sense to build some of the more useful features that Flash brought to the web in the late 90s and early 2000s into the native languages of the web, such as HTML, that have universal support across all browsers (because browsers' entire job description is to take HTML and turn it into a web page, therefore all browsers should handle HTML in roughly the same way). Because these standards are open-source, anyone with the knowledge can look at the code behind the scenes and make changes, and similarly can spot potential vulnerabilities and fix them before they become a huge vector for malicious actors. The basic gist is that we used flash despite all of its flaws because there was nothing better at making things like Youtube or Newgrounds work, but now you can do pretty much everything you would have done in Flash with HTML, WebGL, and/or WebAssembly, so switching to that is preferable."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfseik
|
why aren't all cables and connectors "radial" like RCA or headphone jacks?
|
USB-C was created, and one of its main attractions is being reversible, as in having two ways to being plugged in. However, why didn't USB make a standard that's circular, as to allow "360°" of ways to plug it in, similar to headphone jacks or some laptop chargers? Same things for other connectors: HDMI, mains plugs, etc.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvzjvj6",
"fvzm0qb"
],
"text": [
"Most radial connectors (RCA, coax, BNC, SMA) can only carry 1 signal channel at a time. The headphone connector can carry 3 but at the cost of a longer plug. The USB-C connector carries 12 separate channels copied on top and bottom for a total of 24 connections. It's also shorter and more compact than a headphone connector.",
"Before any USB connector existed, computer perhipherals had different styles of ports, such as parallel or serial ports. These were, essentially, the proto-USB in that they took a lot of different functions of a machine that each required an electrical signal to operate and made one plug that the user had to deal with. But for, say, a printer, having the wire that told the inkjet when to spray and not spray ink go into the data port that was designed to tell the paper rollers to move the paper up to be under the inkjet would be like if you tried to steer a car but your nerves thought your feet were your arms: it wouldn't go well. USB was a minaturization and standardization of these different designs (USB = Universal Serial Bus), and part of that is that each little pin in a USB connection serves a purpose but can also be used to \"ask\" the connected device what pins it did or didn't need for controls. The big problem we had with USB, (in)famously, was the \"flip the damn thing over 3 times before it goes in\" problem. USB's plug was a good compact design, but bad in terms of the application of the design philosophy that if there's only one way to plug something in correctly, the plug should be obviously asymmetrical. The original Mini- and Micro-USB connectors tried to fix this by having an obviously asymmetrical plug, but it still caused some issues with its overall shape and structural integrity. USB-C fixed this by allowing for a symmetrical design, at the cost of slightly more complex cabling having to happen to get that working properly. As others have said, making a completely radial port works best for connections that require one and only one signal (even stereo sound is a bit of a kludge to get older headphone jacks to accept new stereo headphones), and a serial bus (universal or otherwise) by its very concept is never going to meet that criteria."
],
"score": [
12,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hftpha
|
How does a major breakthrough in science happen? Is it because noone has thought of it that way? Are there major breakthroughs in the future of medicine and technology because noone thought of it that way?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fvzte8t"
],
"text": [
"Not necessarily. In some cases, like Einstein's relativity, it could very well be what you said, no one had thought of something that way before. In other cases, it may be that the theory had always predicted something but the breakthrough is finally finding evidence that definitively supports a theory - this is like the discovery of the Higg's Boson 7 years ago. It was theorized that this particle should exist but an experiment finally found strong evidence of it. The same goes for medicine and technology. There are sometimes just brand new ideas perhaps spurred on by new materials or methods (like better computers). More often, the breakthrough was something that the people working on it had wanted to achieve and finally found a method that worked. Since science is pretty advanced nowadays and computing tools and simulations are pretty powerful, it is rare that breakthroughs are something someone stumbles upon by accident. It is much more likely that breakthroughs are the result of painstaking and exhaustive and deliberate effort by a team of experts."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfuqz7
|
Why do digital movies not have chapters to skip to like a DVD would've had?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw001l8",
"fvzy8b6"
],
"text": [
"Because they remember where you were when you stopped watching - DVDs didnt do that back in the day.",
"They sort of do, on services like Netflix where you can skip intro, or skip preview. Honestly though I think the reason digital movies don't have that, is because the standard format like mp4, avi, and more don't have a way to support it. You'd need some sort of external file to keep the information about chapters and the player would have to support skipping to it. Similar to how subtitles files are separate."
],
"score": [
25,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hfwjoa
|
why did people have to stay still for so long to get pictures taken and what happened if they moved?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw0a7j5"
],
"text": [
"Old film emulsions (the part that records the image) were not very sensitive to light, so the shutter had to stay open for very long to get enough light to form an image (otherwise it would be way too dark). So people had to stand still for longer. If they moved, it would just look like a motion blur, or like a ghost-y figure. That's why a lot of old photos have a decent amount of blur/ghostiness to them. Nowadays digital camera sensors have been engineered to be a lot more sensitive, so you can take the same picture much faster and you can freeze the subject that way, rather than having them stay still for a long time."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hg0ulj
|
How come opening and closing credits on some older movies seem to shake slightly?
|
Recently watched The Highlander and Tango & Cash on different streaming services, and noticed the credits move very noticeably. Is it something to do with the transfer from film to digital, or the size of the screen, or...?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw13uq2"
],
"text": [
"It is because of the old technique of attaching credits to physical film. See, credits aren't actually a filmed thing. They are created on film by hand, which even with the most precise measuring tools were never perfectly aligned with the next frame of the film. This lead to a slight barely perceptible wobble in the words. Now many other films have adopted a similar effect for their credits even though the technology exists to make them perfectly aligned. It just gives an old timey feel to the credits. Which is the case for your specific movie, I don't know."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hg5bip
|
How does LTE work and what makes it faster than my WiFi?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw1wofh"
],
"text": [
"Its not faster then wifi. Then again... Wifi and LTE are different terms, they are labels. Wifi is wireless fidelity, the name used for the IEEE protocol 802.11 aka Wireless ethernet. Theres 802.11 Rev A, B, G, N, AC and AX. most of them operating at 2.4Ghz and 5Ghz.. The latest evolution is AX which is also known as Wifi 6 which can use 20mhz, 40mhz, 80mhz and 160mhz channels to provide up to 1Gbit/sec in short distances (or was it 3Gb, not sure), it also improves distribution of bandwidth between several devices connected to the same access point. LTE aka 4G aka Long Term evolution was the winner of the 4G selection process, Wimax and WiBro were also candidates, it can operate from from 450Mhz to 3.7Ghz depending on the frequencies allowed in the country and assigned to the Telco in question, Now what you have to understand is mash mode and stand alone mode. Now most Wifi AP´s work in stand alone mode, meaning they regulate bandwidth and connections to devices individually and have their own network ID, While most commercial networks, both Wifi and Cellular work in Mash mode, which means that the AP´s or the Cellular antenas work in a network in which they manage bandwidth and connected devices collectively through Access controllers which manage the clients and bandwidth users and also allows you to move between cells and AP´s without losing the connection (seamless handovers) so basically, really depends on what wifi and what cellular technology you´re using, sometimes wifi is faster and sometimes LTE is faster."
],
"score": [
6
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
hg7yk0
|
How do "long exposure" pictures work?
|
I've recently seen a lot of these and they seem so cool.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw29e5g",
"fw29sfu",
"fw29wbd",
"fw2fvj9",
"fw2y03i",
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"text": [
"A camera-- to simplify-- takes in light to create an image (much like our eyes). A long exposure just keeps that eye (the shutter) open longer, so that more light gets processed into the final picture.",
"Imagine you have a grid of buckets, covered by a retractable roof. If you retract the roof while it's raining, the buckets will fill up with water. Suppose it's only raining over a very small region. Only the buckets under the rain will fill up, while the other buckets won't. Now, consider, what if that small region of rain is moving. If you open and close the roof very quickly, the rain won't have much time to move and only a few buckets will be filled. But if you open it, and leave it open, you'll see all the buckets it passes over will get filled. You'll end up with a trail of full buckets, even though the source was smaller than that area. This is more or less how cameras work, but with light instead of water, and sensors (or film) instead of buckets. In normal photography the shutter is only open for a fraction of a second, in order to get a clear picture with no motion blur. In long exposure photography, the shutter is open for a longer period of time, which will show moving objects as streaks.",
"When you take a photo, the camera opens a shutter and exposes the photo sensor (or film in older cameras) to the environment for a brief amount of time (typically fractions of a second.) The light being reflected off the subject is captured during this exposure. A long exposure photo is one that opens the shutter for a long period of time (typically for longer than a second.) The longer exposure allows the sensor (or film) to capture more light information than previously possible. This leads to the streaky and blurry nature of moving items and seemingly too perfect stillness of non-moving items. It can also cause certain parts of the photo to turn white as the are exposed to too much light and lose their color reference/context.",
"Others have already explained to you how photography works. The bucket /water comparison is very apt. I will be specific to your question. By long exposure photography if you are referring to the silky smooth water type photos, then try this exercise. Draw extremely close dots on a paper, as close as possible. Now just step back a little and what you will see is a line. So when the camera sensor is exposed for a longer duration, say 10 seconds, the light from each water/cloud particle is recorded in multiple positions due to it moving relative to camera. Hence the outcome is a smooth line in the final image. That's similar to how video works too. When shooting in high FPS/slow mo, each position of the moving object in time is recorded more frequently than say normal 30FPS. Hence while a fast movement may seem jagged/ choppy in 30FPS, it appears smooth because there are many more 'points' of capture and hence your eye perceives it as smooth.",
"Great book very easy to read called \"understanding exposure\" you should give it a read if you're interested in photography.",
"Cameras record a slice of time. The size of the slice is the shutter speed. Most slices are smaller than 1/60th of a second, all the way up to 1/8000th of a second. Because the slice of time is so small, very little to no movement occurs. It looks like everything is frozen. Long exposures are a much larger slice of time — usually a second or more. All the movement that happens during this time is recorded. You're seeing the past and future all together at once. That's why star photos look like circles — you're that star at every possible point it occupies during that slice of time all at once!"
],
"score": [
414,
78,
13,
4,
3,
3
],
"text_urls": [
[],
[],
[],
[],
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}
|
[
"url"
] |
[
"url"
] |
hg8cf8
|
Why are some games' default resolution 1280 by 720?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw2bv11",
"fw2fwne",
"fw2daqp"
],
"text": [
"That is one of the most common ratios you see among TVs and monitors being produced nowadays,and it is a high enough number of pixels to produce a pretty good-looking picture even if stretched out on a very big television.",
"It's possible that the programs in question are improperly detecting your hardware so it guesstimates that resolution as being within the realm of your system providing at least 60 FPS to hit that standard 60hz refresh rate for vsync.",
"Because that is likely the resolution it would run on a console like an Xbox or PS4. The other comment may be sort of right (though I think 1080p TVs and monitors are quickly outnumbering 720p) but the game should be able to detect the resolution your computer is using and scale to the actual screen you have connected. Another possible reason is that out of all the settings, resolution has the biggest impact on performance. This is an easy way to make sure the game runs OK even if the computer isn’t that powerful. People who are familiar with all the settings and have a nice computer will be less annoyed by needing to turn this setting up... compared to people who aren’t familiar with the settings and have a cheap computer, who would find it runs like garbage and might not know how to fix it if the default resolution/settings were higher."
],
"score": [
4,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hg9ua9
|
Why are keyboards aranged the way they are?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw2l9l6"
],
"text": [
"It stems from typewriters. Placing the most used keys as far away as possible from each other allowed for more time between keystrokes, so the mechanism is less likely to jam."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hga2tm
|
what are IP and IP addresses and how does the tor browser helps to hide it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw2n2vc",
"fw33mix",
"fw2zsdl"
],
"text": [
"Think of it as almost a mailing address: if you know the IP of a computer (DNS exists to help here for most internet traffic), you can send a message to that computer. TOR sends all traffic through at least three \"middlemen\" nodes between the source and destination with layers of encryption. Even if you captured the packet at some point, the contents along with the true source and destination will impossible to figure out. [Source computer sends packet to middleman A, who routes it to B, who routes it to C, who then unveils the last layer of TOR encryption and sends it to the destination]",
"Network Engineer here. Inside a computer, everything you get presented to you is, under the hood, a binary number. Text, Colors, Fractions, everthing. That also applies to the algorithms and protocols which govern how networks operate. TCP/IP is a group of protocols which specify how the base layer of the internet works, and IP (version 4, I'll get into version 6 in a bit) stands for Internet Protocol. Briefly, each IP address is a 32 bit number, which, in order to work to connect everyone in the world on the same network, needs to be unique. So, for example, URL_0 might have the address might be 2540011916, in decimal format. But the computer sees it as a binary number, a sequence of 32 ones and zeroes, like this: 10010111011001011000000110001100 A quick aside here: Binary numbers is a method of denominating numbers assuming that you only have two numbers in each digit. Our normal counting system is decimal, which has ten numbers in each digit, zero through nine. But the actual quantity the number represents does not change. They represent the same total value. Binary isn't very useful for humans to read, so that figure is broken up into smaller numbers separated by dots, called the dotted-decimal format. It takes each 8-bit chunk of the 32 bit number, and converts that into decimal format. And that gives you an IP address which looks much more familiar: 151.101.129.140 Now, if you're clever, you'll already realize there is a problem. There are only so many unique totals in a 32 bit binary number, specifically 2 to the power of 32. That total number of unique numbers is: 4294967296 Or just under 4.3 billion unique addresses. Well, since there are more than 7.5 billion people alive, and we have more internet-connected devices than one per person, we are running out of space in the address space. There have been two fixes, or more accurately, one fix and one work-around. The work-around is something called NAT, or Network Address Translation, which permits certain chunks of the IPv4 range to be re-used as private networks, and then those private networks can be *translated* to a smaller set of unique public IP addresses. These private IP ranges are what are normally used in your home network, or at your office, or anywhere you don't need or want the outside world to be able to initiate communication to your systems. The fix is a new version of IP, called IPv6, which instead of using a 32 bit binary number to define the range of numbers, uses a 128 bit number. The total number of unique addresses in that range is so big, I can't readily compute it, but it's somewhere north of this number: 3400000000000000000000000000000000000000 With that range we could assign a unique IP address to every atom on the surface of the Earth, and still have enough addresses to do another 100+ Earths. So no more running out. But again, that 128 bit binary number, or that absurdly long decimal number is very hard to read, to IPv6's \"human readable\" display format uses hexidecimal pairs, or base-16 numbers to render them. The numbers in a hexidecimal digit range from 0-9, and then A,B,C,D,E,F for 10, 11, 12, 13, 14, and 15. So an IPv6 address for URL_1 would look like this: 2607:f8b0:4000:80e::2004 One thing to note is that there is a space-saving convention in IPv6 to turncate zeroes out of the address to make it shorter. That's what the :: notation means. The range of digits between the colons is padded with zeroes, so written long-form, the address is actually this: 2607:f8b0:4000:80e0:0000:0000:0000:2004 And the computer sees it like this: 00100110000001111111100010110000010000000000000010000000111000000000000000000000000000000000000000000000000000000010000000000100 How IP addresses are used, divided up into chunks, and otherwise how your network traffic is delivered to where you want it to go, and the replies sent back to you is a much longer essay, and this one is already getting long enough, so let's get onto your second question: > how does the tor browser helps to hide it? Humans like names, not numbers, and to facilitate mapping names to IP addresses, another protocol was created for the internet called DNS or Domain Name Service. This is a distributed database scheme where a central authority can manage who owns unique domain names, and then the owners of those domain names can present the addresses mapping to each name so that the computer can look up the binary number it needs to find where you wanted to go. There is (usually) a tool on your computer you can use to test DNS, called nslookup, short for name service look-up. So, when I looked up URL_0 , opened my command prompt, and typed: C:\\Users\\Deadfyre > nslookup URL_0 Server: homeportal Address: 1200:180f:ed08:6370::1 Non-authoritative answer: Name: URL_0 Addresses: 151.101.129.140 151.101.65.140 151.101.193.140 151.101.1.140 The first chunk in the response is the name and IPv6 address of where my computer is asking the DNS system for answers. The second is the answer for the query I asked, \"What is the IP address of URL_0 ?\" The second chunk is the answer. You see the name I asked for, and four different IPv4 addresses, any one of which will work if I want to make a connection to URL_0 . Last question: > Also is there a way to change or alter one's IP address? Yes! Network administrators do this all the time. Typically on home networks, as well as networks managed by consumer internet service providers (like your Cable or Phone company) use another protocol called DHCP or Dynamic Host Configuration Protocol, which is a mechanism by which your computer or router can request an IP when they join a network, as well as that critical DNS resolver used for mapping names to addresses, and also the \"gateway\" address, or where traffic should be sent when destined for the internet. In essence, DHCP uses a broadcast message to request that the network send back its IP address, DNS, and gateway information, and the network, if properly configured, will relay that request back to a server which keeps track of those assignments. I hope this answers your questions, and feel free to ask any follow ups, or let me know if you'd like clarification on any particular topic.",
"Think of an IP Address like when you walk into a restaurant and they hand you a little sign with a number on it. Everyone gets a unique number, so when you order something (or ask for something) they know where to send the answer. But if you revisit the same restaurant tomorrow you might get a different number. With Tor, when you order something you don't give them your table number, but instead put that number inside of a bag (which has someone else's table number on it). They deliver that order to the number on the bag, and that person opens the bag and sees your actual number on and brings it to the right place. Kind of like that only several bags deep, and cryptography involved such that only the table that gets the bag has the ability to look into the bag."
],
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13,
7,
4
],
"text_urls": [
[],
[
"reddit.com",
"www.google.com"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hgawac
|
Why do phones not pick up their own noise when on speakerphone?
|
This isn't an issue any more. But I remember old cell phones from when I was younger, the microphones would pick up noise from it's own speaker and make the call echo. What mechanism is in place that prevents this nowadays?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw2szhk"
],
"text": [
"Long story short the phone knows what is coming out of the phone and ignores it when recording sound Basically it still does pick it up on the microphone but the phone knows that it is an echo so it cuts it out of the playback."
],
"score": [
97
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hgcuko
|
How do the software and hardware interact with each other?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw38adb"
],
"text": [
"So, you have microcontrollers, which are essentially low-cost, low-power versions of the CPU inside your computer. These microcontrollers have registers that are can store small amounts of information. When you write code, the instructions essentially get distilled down into operations that manipulate the information inside of these registers. Now, microcontrollers also have output pins. These pins are at a specific voltage level. When you set certain registers within a processor, you can set these pins to be a high voltage. When you connect these pins to external devices, you can send signals to these devices to perform certain actions. In reverse of this process, you can have analog sensors that send some information to your microcontroller. The microcontroller has input pins that are connected to an Analog to Digital Converter (ADC), which measures the analog signal being sent to the microcontroller, and stores this value inside of a register that can be read by the processor. EDIT: When I say high voltage, I mean a logical high. Computers operate on 1s and 0s, and a high voltage represents a 1, and a low voltage represents a 0. EDIT 2: If you’re working with analog devices, there is also something called a Digital to Analog converter which reads from a register in the microcontroller and outputs an analog voltage instead of just a high or a low."
],
"score": [
3
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
hgf114
|
If led light bulbs are so efficient, why do they need fairly large heat-sinks? I thought the advantage of LED's was heat isn't a major byproduct.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw3ko9j",
"fw3kv1c"
],
"text": [
"It isn't, compared to incandescent bulbs. 95% of an incandescent bulb's energy consumption goes towards producing excess heat and IR light, and only 5% goes to making visible light, whereas with LEDs about 3x as much of the energy consumption is converted to visible light. There's still heat to dissipate though, but this is the other bit: With an incandescent bulb, the part that gets hot and the part that gives off light are one and the same, and heat can't effectively be pulled to a heat sink without it. In LEDs, the diode itself doesn't heat up when emitting light, but the other components do. Not as hot as an incandescent or halogen bulb, but the heat does need to get bled off through a heatsink.",
"The LED bulb does generate a lot less heat, but its also a lot less tolerant of the heat An incandescent bulb is 2-3% efficient, so your 100W bulb generates around 97 watts of heat and non-visible light. The filament in a bulb like this is generally up at 3000 degrees while the glass bulb itself can be 200-250C which is insanely hot to the touch LED bulbs are about 20% efficient so that 100W equivalent bulb needs to produce 3 watts of light so its 15W of input power. But it cannot tolerate close to the same level of heat as the glass bulb can, it really needs to keep its internal temperature below about 85C for the electronics to have a long lifespan. Heat transfer is proportional to the difference in temperature. If you're running an incandescent bulb at 240C in a 40C fixture then its going to transfer heat 5x faster than an LED bulb running at 80C in that same fixture. LED bulbs have gotten *a lot* lighter as the switchers used in them improved in efficiency and reduced the heat generated internally, but they'll always be far more sensitive to heat than a hot wire in a glass jar."
],
"score": [
10,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hgg8xl
|
How did Greeks measure time
|
I was just watching a video, currently over on /r/videos with Carl Sagan explaining how the Greeks knew the earth was not flat, over two thousand years ago. The explanation being that two posts at different locations had different shadows when observed “at the same instant.” That phrase had me curious. I’ll assume the distance between sticks was more than shouting distance, so how did they determine the exact same “instant”. Did they have functional clocks or something, did they flash mirrors at each other? Video was [ URL_0 ]( URL_0 ) (And I’m not a flat earther, just to be clear!!)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw3x1cz",
"fw3rfy2",
"fw3rtur"
],
"text": [
"As I recall, it was two scientists of the day agreeing on measuring the shadow at their respective places when the sun was highest on a specified day. Easy enough to find out as it would be the time of day that the shadow was shortest. The time wouldn't even have to be exactly the same, but it would be most accurate if at the same longitude. Then depending on your latitude, the length of the shadow would be different.",
"I could be wrong but I think it was through astronomy. The sun and stars change their position in the sky as time goes by, but they return to their position after a year has passed. Constellations could be used to remember stars. Their concept of time probably wasn't broken down into minutes and seconds like ours. Sunrise, midday, evening and sunset would be more like it.",
"Water clocks! Imagine a narrow funnel filled with water on top of a measuring cup that measures the drips. Let's say that you know it takes exactly 15 mins for all the water to slowly drip from the funnel into the cup. Then you can keep track of how much time has gone by! Cool picture of a badass looking water clock: URL_0 Edit: I think that the other poster is right that sundials were used a lot, too! I thought that they are harder to calibrate for precise things? But it's not something that I know much about!"
],
"score": [
7,
4,
3
],
"text_urls": [
[],
[],
[
"https://images.app.goo.gl/jaQDL5o3e1Mohm4ZA"
]
]
}
|
[
"url"
] |
[
"url"
] |
hgi0s8
|
How does an Ip address work and how accurate is it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw43685"
],
"text": [
"An IP address is a unique identifier for every machine using the internet. Known as your “internet protocol address,” this identifier is written as a string of numbers separated by periods - google ^ Not sure what you mean by accurate, if you're speaking geographically your external IP can be accurate down to the city or block and will tell you who your internet service provider is (ISP). ELI5 version - your pc's internet name that can tell others where you are from."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hgkrb5
|
With the science we have today, if someone set themselves to building a T-800 Terminator like in James Cameron's 1984 movie, would it be realistically feasible? If not, what scientific knowledge/techniques are we still missing?
|
Primary components are: a.) Mechanical, battery-powered, bullet-proof metal skeleton substantially stronger than a human being. b.) Cloned human tissue capable of self-sustaining with a non-organic energy source. c.) Artificial intelligence able to interact with the real world. Seems to me we are reasonably close to all three. Any chance of seeing actual Terminators within our lifetimes? (Sorry for the nerdy question, was just curious).
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw4l2x1",
"fw4ler7"
],
"text": [
"Protecting the power supply is the biggest issue The amount of batteries required to power a frame capable of the tasks would be excessive. That's why the Boston dynamics bots have their backpack looking compartments. Robots like Atlas already exist, but would go down about as easily as a regular soldier.",
"The first obstacle would be power. There's no way you could power that robot with any known technology. You'd need something like a micro-reactor - and that's not even on the horizon. The second obstacle would be the sort of generalized AI it possesses. When we talk about 'AI', we're really talking about a number of statistical techniques that *seem* smart because the math underlying them is far too complex for any human being to process. But they're not actually 'intelligent'. It's just a lot of math. The third obstacle would likely be sensors. We can do cameras and audio pretty well. We never see the Terminator doing anything with smell/taste, but we can't really do that - the best we can do is very specific chemical sensors (which tend to have a limited life span due to the destructive nature of the sensing). A full-body touch sensor would almost certainly be impractical with current technology. However, sensors is probably the closest of the problems I've outlined."
],
"score": [
8,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hgq7bt
|
DrDisrespect banned from Twitch
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw5gq1y"
],
"text": [
"It is still unfolding so not that much has come out yet. Dr Disrespect was fairly abruptly permanently banned from twitch as well as losing his verified status on discord. This has let to wild speculation ranging from sexual assault/harassment, tax evasion, racism, breaking his contract, and more. Remember these are all speculations and the reason why is currently not known by the public. The reason behind this will likely drop at some point through either a public statement or a leak from a source. But for now, there is not enough information to form a solid conclusion."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hgt743
|
How does YouTube know to stop playing videos when your phone is locked? Why is this not a feature we can just turn off?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw63ueu",
"fw5wtwg",
"fw6dded",
"fw6cmx8",
"fw609jg",
"fw5x0fu"
],
"text": [
"It's an artificial restriction. There's no reason it has to happen, except to sell you the ability to stop it. Use the NewPipe app instead, and you suddenly won't have this problem.",
"The YouTube App, like most apps, are connected to your phone's state (locked/unlocked, on a call/off a call) by both Permissions and other code. YouTube, specifically, *can* continue videos while your phone is locked. But in order to unlock that functionality, you have to have YouTube Red.",
"Open Youtube in your mobile browser, switch to desktop mode, minimize the browser, hit play on the overlay, lock your phone. You can now listen to Youtube videos with your screen locked.",
"everyone talking about ads is forgetting that ads aren't just pictures. there is nothing stopping youtube from playing audio ads when the screen is off, the reason google decided to remove this basic functionality is so you'll pay the ransom to get it back",
"Why YouTube doesn't allow you turning off this feature ? All the videos in youtube are stored and played in your app or browser with the help of a bunch of computers (servers). Running these computers requires costs which youtube is incurring. YouTube needs money to support these costs. One way they can earn this money is by showing you ads, but when you lock your phone, they can't show you any ads, and hence can't earn money. So, they stop the video once you lock the phone. Another way they can earn money is by you paying money for their services. YouTube Red is the paid subscription provided by YouTube. If you purchase YouTube Red, they will allow you playing songs even when your phone is locked. How YouTube app knows that you have locked your phone ? All Apps in mobile given enough permissions can know what actions are you performing on your mobile. This is necessary to provide you essential features in various apps. YouTube listens to these actions and turns off the video.",
"Because Youtube doesn't want to be used as a music streaming service. It cost Youtube money when someone watches a video (because they have to build and power a massive infrastructure to deliver all those vids), but they don't make as much if people don't look at ads on the site, or click through ads, which you can't do when the phone is locked."
],
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43,
24,
6,
4,
4,
3
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"text_urls": [
[],
[],
[],
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|
[
"url"
] |
[
"url"
] |
|
hgtvsk
|
why do games take so long to load in files that have already been loaded in
|
Like, in a parkour style game like mirror's edge for example, if you fall down, you have to restart, which takes super long. But if you were already standing on the roof that you respawn on and everything was loaded in around you, why does it still take so long? I know I might have described my question badly but I did'nt know how else to word it
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw60cvy",
"fw6ahan"
],
"text": [
"Usually due to lazy programming, games will often just dump the contents of the level and start loading it over again from scratch. This is easier and faster than writing the logic to clear out the pieces of the level that are unnecessary while retaining those that are.",
"Depends on the game but even in an ideal situation where the game is not reloading everything, If you enter a level and walk a distance, the graphics from that entry point have been unloaded to make room for the area you walked to."
],
"score": [
10,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
hgty33
|
How do cds work? I know that they have all the tiny grooves but how do those get turned into information such as music or video games?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw624su"
],
"text": [
"Music, images, text, videos, code; we've figured out how to encode all of these types of media as long strings of binary digits. Text is an easy one to think of, we say that the letter A is encoded as the binary number 65, B as the binary number 66, and so on. Images are encoded as numbers representing the color values for each pixel. Sound is just a wave where we use numbers to define the height of the wave at sampling points in time. Video is just a combination of many images along with sound. Code can be in many forms, either as text or bytecode where small sets of bytes serve as atomic instructions that tell the CPU what to do."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hguc4m
|
How is a video converted from 30fps to 60fps even though the camera was only capable of filming 30fps? Saw a remastered video of the lunar rover and was curious.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw63r6f"
],
"text": [
"They use computer algorithms that take two neighboring frames and try to draw an approximation of an in-between frame. [The result is not always super pretty, especially on animations and quick snappy movements]( URL_0 ), often causing deformation and wobbling in the interpolated frames. The more consecutive frames you ask the computer to bullshit into place and the more different the two original frames are, the weirder the output can get."
],
"score": [
5
],
"text_urls": [
[
"https://www.youtube.com/watch?v=a-pyRiPVzto"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hguwp3
|
How do websites generate so much revenue from ads when most of us hardly click them. Wouldn't that be a loss to the the original company investing in ads when most of them are left unclicked?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw671ud"
],
"text": [
"So there are generally 2 types of advertisements on the internet. Pay-per-click (PPC), and Pay-per-impression (PPM), and they work on two different theories. PPC ads are just that. You might see that ad on a website, but the website owner doesn't make any money until somebody clicks the ad. Because of this, smart website owners who host PPC ads try to target which ads appear so that it's things that will work for their visitors. (example: a camera review site might have ads for cameras, and adobe ads for photoshop. Both things that are in the sphere of their target audience) PPM ads work on a different theory - that if you repeatedly are exposed to a brand/product, that you'll develop more interest over time. It can take several times before somebody really starts to gain interest in something, so PPM ads show up more to hit that \"Oh yeah, I've seen this before\" response in our brains. While the tangible click of a PPC ad is not there, it's a brand awareness type thing so is effective in less quantifiable ways. You tend to see PPM ads more on places like FB, some of the reddit ads, etc."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hgv3gq
|
Why do most TV remotes require 2 batteries to work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw68cdt",
"fw68yx4"
],
"text": [
"Each garden variety AA(A) zinc-carbon battery outputs 1.5V on a good day, and more like 1.2V later in life. This is a kind of shitty situation, because the transistors inside most cheap modern microcontrollers work best on 3.3V and [complain if you don't give them at least 1.8V or so]( URL_0 ). The infrared led that actually gives the signal also has a *forward voltage* (minimum voltage at which it deigns to give you the time of day) of 1.4-1.6V so a single slightly used battery would be very unreliable at making it light up. So yeah just stick two batteries in series, gets you 2-3V, everybody's happy.",
"An IR diode needs around 1.5V forward voltage. So it might work in a fresh battery but when the voltage drop you need to add some voltage boost circuits but makes them cost slightly more. With 2 batteries you are around 3V when they are new but down to 2 V or less when they get drained. So you make them as cheap as possible and use 2 batties instead of more components and one battery. A remote with a single 3V button cell battery would work fine and they are common for very flat remotes that are not for a TVs. The TV manufacturer has cheaper and more common batteries in them because you do not have a size limitation. A TV remote need lot of button and to have some thickness is an advantage as it lay better in your hand."
],
"score": [
43,
3
],
"text_urls": [
[
"https://wompampsupport.azureedge.net/fetchimage?siteId=7575&v=2&jpgQuality=100&width=700&url=https%3A%2F%2Fi.kym-cdn.com%2Fentries%2Ficons%2Ffacebook%2F000%2F029%2F447%2Fman.jpg"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh05ua
|
Why is the data TikTok collects an issue for its users?
|
How is this different from other companies and why should I care? I get the whole “privacy” issue but then again, why should I care about privacy? What are the implications of this data being used against my best interests?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw78d9d",
"fw7arss",
"fw734v4"
],
"text": [
"Hypothetical situation. You have the app. You're recording that you hate China. This data is sent to China. They have your face, location, phone info, contacts, and every background image of your house. You decide to one day go to China. They have your facial data and detain you when you land. Now take that info and remember that Military personal were using the app in classified locations, plane cockpits, bases, etc. That information can be used against the Military later.",
"If you \"get\" the whole privacy issue but don't understand why you should care, then you don't don't \"get\" the privacy issue. Privacy is essential to autonomy and the protection of human dignity, serving as the foundation upon which many other human rights are built. Privacy enables us to create boundaries and protect ourselves from unwarranted interference in our lives, allowing us to negotiate who we are and how we want to interact with the world around us. Privacy protects us from arbitrary and unjustified use of power by states, companies and other actors. It lets us regulate what can be known about us and done to us, while protecting us from others who may wish to exert control. Many of the failings of modern civilization today was enabled by the complete lack of discretion of the masses, informing the enemies of the people the who, what, and how to manipulate public opinion, decide elections, protect the wealthy, and divide the populace.",
"It isn't even the data. The latest report implies TikTok weaponises your phones for DDoS attacks and other shitty stuff and can then wipe it clean."
],
"score": [
8,
7,
6
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hh3fwq
|
How do companies, like mobile phone companies, make sure every mac address is unique?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw7oylm"
],
"text": [
"Blocks of MAC addresses are assigned to the companies that make the modems and ethernet controllers, you can even [look up who has what blocks assigned to them]( URL_0 ). Each block gives 16.7 million unique addresses and its up to the manufacturer to ensure they are giving each device a unique ID or you can end up with some interesting issues Most companies will have a similar system for managing serial numbers on devices so managing unique MAC addresses as well isn't a new problem"
],
"score": [
6
],
"text_urls": [
[
"https://www.macvendorlookup.com/browse"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh3or8
|
So how do multiple monitors work on the same computer?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw7pq63",
"fw7r1g6"
],
"text": [
"Ok... first off, the computer acts/thinks it’s one screen... even though it’s physically 2 or more screens it acts like it’s one and that’s why you can move your mouse continuously across all screens. In the settings of your computer/laptop you can even tell it how you’ve set up the screens... like next to each other or on top of each other etc and it will act like it’s one big screen in the configuration you set.",
"> How do you get the different monitors to display different things if it’s only one computer? The computer has separate outputs for each monitor. Since they are plugged in separately, the computer can control each display independently. > How do you use the same mouse and keyboard across all of them? For the mouse, you tell the computer how the monitors are arranged. For example, let's say you have 2 monitors: monitor 2 is to the right of 1. In your computer settings, you would specify this layout. Then, if you move your cursor all the way to the right side of monitor 1, the computer knows to move the cursor to the left side of monitor 2. For the keyboard, you control the active window as you normally would. Just select whichever window you are using to type in it."
],
"score": [
7,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh5n15
|
How does a computer/game console/electronic device (not with internet or radio access) STILL know the exact date and time after being out of charge/turned off for an extensive amount of time? Eg years and years
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw81ky9",
"fw81l3a",
"fw85k3y",
"fw881t9"
],
"text": [
"They have a tiny battery inside, and that battery just runs an internal clock, so it uses almost no energy at all, and can last for years, because modern clocks are really energy efficient.",
"Lots of electrical devices, especially game/computer systems have small watch batteries on their motherboards that does very little other than run a clock and wait for an on signal. Even old video game cartridges had one inside.",
"Usually they have a tiny battery inside that just runs the timer. Ask a techy friend to detach a \"CMOS\" from a desktop motherboard, you'll see that the time and date of the system will restart to 01-01-1970 because that is the \"start date\" of most system units.",
"Just adding to what other have said, the battery they are talking about is similar to a wrist watch battery. Fun fact: old console cartridges used to have them to keep your saves stored, like n64 cartridges, which means they will eventually discharge and lose all the data that was there permanently."
],
"score": [
35,
15,
6,
6
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh6kjz
|
How do computer processors work? Is there a limit to how fast they (or other computer parts) can get? If there is a limit, what are the possibilities for moving past this boundary?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw88po6"
],
"text": [
"Processors work by sending an electrical current through a series of logic gates. The major limit here is heat. The faster the clock cycles the hotter it gets. You can make the transistors smaller to a certain limit before you start getting quantum effects, this is to reduce the current needed. Coincidentally, they place more transistors in the same area, leading to performance improvements, but still hitting heat limitations. There's only so much cooling you can really do. If you really want to know the details see URL_0"
],
"score": [
5
],
"text_urls": [
[
"https://www.amazon.com/Computer-Architecture-Quantitative-Approach-Kaufmann-dp-0128119055/dp/0128119055/"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh7yuv
|
How do the coffee machines heat water so fast?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw8hc5i",
"fw8kyan"
],
"text": [
"Very similar to a stove. They have an element that heats up using electricity and that heats the water. There isn't a ton of water being heated, just a coffee pot (or less) full.",
"Its actually not trying to heat all the water you've put in the reservoir. It's only heating a very small amount in a pipe and using the steam pressure to push the water up the into the filter basket. So unlike a big pot of water which you boil for pasta it's more similar to trying to boil a tablespoon of water at a time. This actually has a tertiary benefit. Actively boiling water will actually burn coffee grounds making coffee unbearably bitter. The small amount of steam pushes warm non boiling water up and drops it on the grounds leaving the steam that pushed the water into the basket to cool, condense, and drip onto the coffee grounds."
],
"score": [
8,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hh8jo2
|
Why can my computer copy a 500 MB file easily, but struggles to copy 5 MB of text in a word processor?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw8lriq",
"fw8vi98",
"fw8t3sq",
"fw8vmxa"
],
"text": [
"When you copy a file it doesn't need to put the entire file in memory, and simply needs to copy the exact bits. When you copy in word, it needs to put all the text in memory and then format the text so it can be displayed to you. It's the difference between using the read/write power of your hard drive, and the computational power to format all the text, as well as formating the data in memory.",
"Copying is a simple transfer and it barely bothers a modern CPU. Processing 5MB of text stretches what a word processor can do: the program has to determine number of pages, line endings, page endings, formatting, potentially look at your syntax and grammar, and other things I can’t think of right now. Imagine people moving buckets vs people having to pour the content of said buckets into different size buckets intelligently. Then having to write a report about the content of the buckets, then write some labels for the buckets. Where the labels for these buckets depend on the labels and the content of previous buckets. Pretty lengthy endeavor.",
"When you copy a 500 MB of file, your computer does not process the content of your data. Only read and write your data. However, in word processor, your computer process every single bit of data. Because every combination of 1 and 0 matters and represents something. Word processor needs that combination to be read and processed, so your data look pretty on your screen. Having that said, copying text in word processor requires more memory and processing power.",
"When you copy a file the computer doesn't really do anything interesting with the data. When you copy-paste in a word processor it'll have to look up the correct glyph size for every character, taking into account font, font size, etc that can all vary between any 2 characters, just to know how much space it will take on the page. It will need to check how long words are so it knows what fits in a line, maybe try to hyphenate words to check if that'll help. It's basically a crazy amount of things that need to be calculated, just to tell you how many pages your document will take up and show you an accurate scrollbar. Also 5MB is an insanely big number for text size, so pretty much not what word processors are designed to handle. The bible is around 4."
],
"score": [
28,
11,
5,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hhc12o
|
Why are earphone leads divided, with one being longer than the other?
|
Is there some advantage to it? Ive genuinely never thought about it.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw95jyy"
],
"text": [
"The ones that have one longer lead are designed to go around the back of your neck so when not in your ears they will stay around your neck. Some folks also prefer having the cord off to one side rather than straight down the middle like traditional equal length earphones."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hhcnj5
|
. What is the function of the characteristic sound of a 56k modem dialing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw99bxa"
],
"text": [
"The modems at each end are talking to each other to negotiate a speed. I used to be able to tell the speed by the sound before it fully connected. Once it negotiated, the sound was disabled but I believe, other wise, it may continue. You could also put an AT string in the dial code to silence it at that point too (so dad doesnt know you're on the internet at 10pm)"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hheav0
|
How does a digital camera "know" what to focus on?
|
I tried to find similar answers but none that hit the nail on the head as to how the camera "knows" what to focus on. What I mean by this is how does my camera know to focus on a specific person or thing, when there are countless other things it could focus on. Say, a picture of a person with a stop sign behind and some trees also, how does it recognise the person and ignore the sign and the trees?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fw9je1s"
],
"text": [
"There are two methods for cameras with autofocus... Focusing on the object in the center or at a preset focus area. This is determined by the photographer and/or camera. The newer method uses machine learning for subject detection and selection. What is the photographer trying to take a picture of? Is it human? Does it stand out more than other objects? face detection, etc. Sports photography is slightly different, it’s not machine learning, but uses the chip to track objects once selected so you can burst while the subject is moving and maintain focus. As far as how it actually focuses, there are a couple methods like phase detection or contrast detection of the subject once the camera or photographer has identified the subject."
],
"score": [
18
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hhjg6e
|
How can video game developers go into a specific player’s game, while that person is playing the game, and alter objects or the game itself? Example of what I mean in the desc.
|
The developers of Cluster Truck went into this specific player’s game on livestream and began messing with his game, typing text on screen and changing the colors/speeds of all the trucks. [example]( URL_0 )
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwak88w"
],
"text": [
"As it says in the description of the video “Some people seem confused as to how the developers could've modified the game in the way they did, so I'll try to give a run down of how it worked. Clustertruck has Twitch integration, which is why that bar appears at the top of the stream. Each viewer can vote on one of three options, and one of those options gets picked randomly. Basically, all the game does is look at the Twitch chat, and knows to detect certain words or phrases, and that's why people are able to vote and their votes get detected. So when the developers joined the stream they began typing specific commands in the chat, like commands that turned the truck purple, or changed the gravity. These commands were only used by the developer, and I'd assume they did that by simply telling the code to only acknowledge those lines in Twitch chat if it came from that specific account. I hope that helps clear up some of the confusion.”"
],
"score": [
55
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hhnyn3
|
How an interrupted song on FM radio picks up where it left off.
|
I was listening to the radio in my 2019 Tacoma when my dad called. We talked for 16 minutes. When the call ended, the song that had been playing before he called continued like nothing happened. I looked up the length of the song. It's only 4 minutes long. This has happened more than once.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwb72y7"
],
"text": [
"It looks like it’s a feature in some Toyotas where it’ll cache 20 minutes of radio. Seems like a pretty neat feature. URL_0"
],
"score": [
10
],
"text_urls": [
[
"http://toyota.custhelp.com/app/answers/detail/a_id/8004/~/how-do-i-use-the-cache-radio-feature-in-my-vehicle%3F"
]
]
}
|
[
"url"
] |
[
"url"
] |
hhpbbj
|
What is a transparent proxy?
|
Is it good enough to make IP invisible?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwbfvs4"
],
"text": [
"All a transparent proxy is, is one you don't need to manually configure your browser to use. Generally speaking something inline with your internet path will transparently intercept your traffic and proceed to proxy it. This could be your router, firewall, maybe even your ISP. It doesn't necessarily do anything to mask your IP address, a proxy will often times rewrite the request with its IP address, but if the proxy is truly inline then it is possible to still proxy the traffic while maintaining your IP address."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hhwg3k
|
Why is network bandwidth measured in kilo/mega/gigaBITS rather than kilo/mega/gigaBYTES?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwcn9lf",
"fwcqi7z"
],
"text": [
"Historically, it's because network communication works in bits, not bytes. Bytes are used for storage and memory, not transmission. By now it's simply because using bits instead of bytes sound more impressive (200Mbps sounds more than 25MBps).",
"At this point it is mostly because it sound bigger (by a factor of 8), historically it was because you didn't transfer data in bytes, but bits. When transferring data people who care about the transfer speed weren't really looking at the actual amount of data received as that could differ quite a bit depending on the scheme used. what they cared about was the number of bits that were physically transferred. In practice there was a lot of overhead and redundancy involved some of it on the bit level. There is this whole layer structure where some engineers looked at the lowest level of bits send and received and considered how this was used on higher levels someone else's problem. To be fair it only makes sense to measure the speed of a connection based on the gross bit rate that the connection actually has and not all the other stuff that gets subtracted at higher level that are not the connections fault. It might help to think of it like as hipping company transporting a container full of goods. The shipping company only cares about the weight of the container. The end user after unpacking all the boxes inside the container will receive a lot less stuff weight wise than the shipping company billed them for, but as far as the the shipping company is concerned it is not their fault that 10% of the weight they billed you for turned out to be cardboard and plastic packaging. So the people responsible for the wires only care for the bits that go over the wires, that these bits get assembled into bytes and then 10% of it gets discarded when everything is unpacked at the end is not their problem. Data transfer is in bits and the data you care about receiving is in bytes. There will always be less than one eights of the bits actually making it to your computer as many of them get discarded as packing and filling and shipping labels and stuff. An older measure of data transfer speed was baud. It did not care for bits and bytes, bot for symbols. Symbols can be understood to be mean byte in many contexts so baud is like byte per second, but it is more flexible as you can for example transfer ASCII character with 7 bit be per character and even stuff like morse code can be measured in baud even though it doesn't really use bits and bytes. But most of that is history nowadays advertisers for data transfer stuff talk about the gross bit rate since it is the largest number, when most people care more about how many actual bytes they receive in an standard use case scenario. It isn't helped that there are competing definitions for the use of si prefixes with bits and bytes. Originally engineers decided to use kilo etc to mean powers of 1024 as this was a nice round number in binary. But the people who run the metric system aren't happy about that as kilo means 1000 to them. People who sell hard-drives are happy to use the 1000 definition in their advertising as it makes their stuff sound bigger and some operating system have followed suit. These different defintion makes the question of how many kilobytes of data you get out of a certain amount of kilobits per second of transfer even harder to understand at a glance."
],
"score": [
30,
10
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hhxs4i
|
How do earphones create sound waves that are longer than the size of earphones themselves?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwcz1yz",
"fwdknjk"
],
"text": [
"Sound waves are created from something vibrating and then the waves move out away from that object vibrating. Think of like a water wave. You put a toe in the water and ripples travel out from that point. The wavelength (the length of the wave) is determined by the frequency (rate) of the toe going in and out of the water and how fast the waves goes out from the toe. The width of the toe doesn’t matter for the wavelength.",
"The physics ELI5 is: it can do it because sound waves are [compression / \"longitudinal\" waves]( URL_0 ). In other words - the speaker alternately pushes and pulls air along the direction in which the sound moves. Your ear responds to changes in pressure, and how frequently they arrive. The lower the frequency, the longer the wavelength. So the wavelength basically depends simply on how fast the speaker membrane vibrates - not on its size. The Audio ELI5 is: almost certainly more complicated. Real audio engineering is complex - I don't pretend to understand most of it - and there will be any number of other factors involved in the final design. Sound volume depends on how much energy goes into the wave, for example, and that's related to, e.g., how much air the membrane moves as it vibrates - and a small membrane isn't going to be able to move as much as a bigger one. So a small speaker vibrating slowly can produce a low note, but it's also going to be a rather quiet one. But in principle the physics holds: there's very little stopping a speaker of any size producing a note of any wavelength, beyond its physical ability to vibrate at the required speed."
],
"score": [
12,
5
],
"text_urls": [
[],
[
"https://www.youtube.com/watch?v=kxQj-wPePBU"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hhxysh
|
What incentivise groups to crack games and distribute them? Is there any monetary benefit for them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwcvwul",
"fwcvxev"
],
"text": [
"The technical challenge and the recognition. To a cracker, a copy-protected game is a riddle, a puzzle box, crafted by the best puzzle-makers the game industry can afford. There's a rush and a lot of prestige in being the first to solve this puzzle.",
"It would be a bad idea to collect money for that sort of thing. Cracking the games alone is illegal , collecting payment for the cracked game would actually get someone to do something about it. DRM is cracked most of the time so people can pirate it , but also so that people who bought the game can play it without the DRM that can hamper the performance of a game."
],
"score": [
28,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hhy3ek
|
Why does windows takes way longer to detect that you entered a wrong password while logging into your user?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwdrj7n",
"fwd0h8t",
"fwcvzxh",
"fwd4ucr",
"fwdqfch",
"fwev6qa",
"fwdllqe",
"fwd084d",
"fwd9cl0",
"fwegpcb"
],
"text": [
"Top voted answer ~~is~~ was wrong I'm afraid. It's a nice theory that it takes time to verify the password with an online server, but: 1) In 2020 that shouldn't take more than a few miliseconds. Even if you're on very bad internet. 2) Not all windows accounts are in the cloud. You can have a local account as well and it will show the same behaviour 3) This behaviour also exists in many Linux-greeters (for example the one in Ubuntu also has this delay), and here usually you won't have a password that needs to be checked by a server. So now for the answer: It's what has been mentioned before: it's to prevent people from making several guesses in a row (doesn't have to be a brute force, people can also guess manually for frequently used passwords). Microsoft also claims on their blog that it's to prevent dictionary attacks, contrary to what people claim in the comments below this post.",
"Say you use your Microsoft account to log into your computer. This lets you do stuff like change your password using your online account in case you forget it, then access your computer with the new password. Well normally Windows already knows your “current” password so you can log in quickly, and log in without internet access. But if you enter the wrong password, it goes online to check with Microsoft whether the one you entered was right— the computer thinks it’s wrong, but maybe you changed it, and this is actually your new password. For technical reasons, it is a security risk for Microsoft to *transmit the password to the computer* so your computer can’t know if it’s changed or what it is without checking with Microsoft each time, they just respond with “right” or “wrong”. But when you’re entering a password the computer *already knows is right* — the same one you used before or one you just set on your Microsoft account— after it confirms this one is correct, it will be faster in the future.",
"This is per design. It knows fairly quickly that you entered the wrong password. However if it just gave you the option to type the password again as soon as possible it would allow someone else to continuously guess passwords. To prevent this there is a built inn delay in the password checking so that you can not type passwords too fast.",
"In addition to timing attacks etc, windows does a thing where you login using your Microsoft account. AFAIK it caches the correct password hash locally, so when you enter the correct password it knows immediately and logs you in. But what if you changed your password and that locally cached one is now out of date? When you enter a \"wrong\" password, it contacts Microsoft's servers to see if the password has changed and, if so, whether the one you entered matches the new one. So there's a natural delay while that happens.",
"Hey used to work as a Systems Engineer for Microsoft so I'll give this a try. This tech is pretty much the same at its core since Windows 2000 and although things have changed with Windows 10, in this aspect they still use the same old tech, so the behaviour is the same in so many Windows versions. When a user is prompted to login on Windows they see what's called GINA or Graphical Interface for Name Authentication (gina.dll). This is the username-password prompt that comes up when you press ctrl+alt+delete. What GINA does is take what you typed as a password for this user and compare it to the hash of that user's actual password that's stored in your computer's LSASS (local security authority subsystem) database. So the first time you type your password, GINA checks with a database that's on your system to see if you have the password correct. This takes only milliseconds so it's very fast. Now if you have previously logged on this pc correctly, there should be a \"hash\" of your password stored locally and you're in. If however you haven't logged in recently or you typed the password incorrectly, GINA now needs to make sure that she has the correct password in her LSASS database - afterall, you might have changed your password since the last time you used it on this computer - so she needs to go check to make sure she has the correct password. This invokes another process that checks to see if you happen to have an account on some other computer on the network, typically in work environments this would be another computer called an Active Directory Domain Controller Server or in our days on some server on the Cloud. This additional step requires the computer to send a receive information from your network, and this takes some seconds to execute (can take up to 120sec if you have network issues). So compare the milliseconds that it takes to confirm the password you typed vs the \"hash\" that's stored locally and the seconds it takes to double-check the information from the available networks when your password doesn't match. Hope it's clear enough, feel free to ask anything additional if I can explain it bit better.",
"You know how some websites will lock you out after trying your password (and failing) after so many tries? Well it’s actually very common to do other things too, especially with something like your computer login where just locking you out is not a real option. There is no ‘forgot password’ link for your laptop. One of the things they can do is add an artificial delay before telling the person they failed. This has a few benefits. One of them is that the delay protects against people (or bots) trying to brute force guess. Sometimes the delay is increased with each wrong answer. This can make it frustrating (to humans) or make guessing take way too long for bots. You can’t try every word in the dictionary if it takes a year to do guess them all. The delay can also be useful to try and provide a smoke screen against intelligent guessing. There have been cases where people have been able to use the duration (how long it takes for the password to fail) to help shed light on the authentication process itself. For example you might be able to tell that the password isn’t encrypted very strong if the computer is able to tell in a microsecond that your password is wrong. There are more examples of this. So it’s common for people to inject delays just to make it fuzzy. And the ELI5 for this example: If you ask someone if they like you, and they pause for a while and then say “yes”. Then you can glean some information about their answer. Maybe they don’t really like you at all because of the pause I their answer. Your computer doesn’t want you to be able to read between any lines like this, so they add delays (sometimes variable delays).",
"It takes longer and longer for it to tell you that you entered to wrong password the more attmpts you have made, its a design choice like that phones phones that lock the device when you try too many times, Windows does the same but is a bit more subtle about it",
"A password you type in is checked against the correct password stored in the system. A funny thing, for many security implementations protocols, the amount of time it takes is a based on the amount of correct letters you guess. By measuring the time while guessing, one could work out the password. In very simplified form, if your password is abcde and someone guesses aaaaa vs abcaa, the latter would take 3 times longer to decide it's wrong. So for security reasons, there needs to be a fixed delay, no matter how wrong the password is. Better make that time long enough. All else, the annoyance it generates, making brute forcing more time consuming, are cherries on top. The base feature is that, without this delay, it'd take a few minutes for a computer savvy person to work out your password. & #x200B; This is, incidentally, how they figured out the root password for the gamecube and the wii, for example.",
"Basically, there are a couple methods that your computer can check to see if you typed the right password. Your computer doesn't store your password...in fact, no system in this day in age should. Instead, when you type in your password, it \"hashes\" your password, meaning it runs a math operation on what you type to create a random string of characters. This math operation is one way, so you can't \"undo\" a hash. When you try to log on, first it checks locally if what you type (after it is hashed) matches what it has stored locally. For most consumers, this is the only place the password hash would be kept. However, with more and more going \"to the cloud\" and online, increasingly you see your windows account now bridging into Microsoft store, windows store, Xbox, etc. For corporate users, their computers are often joined to a domain, either on premise (they have servers at the office that your computer needs to check in with) or hosted in the cloud (Microsoft Azure or some other option like that). So now, if what you type locally matches, you're done. But if it doesn't, well...maybe you changed it online. Let me check with Microsoft. Or maybe you changed it at the office. Windows then has to check with all other possible places that may have been updated that hasn't necessarily been passed onto the local machine. There are time frames that each of these queries can take, and often not an insignificant amount of time has to pass before Windows gives up or realizes that it can't reach somewhere or it gets back the rejection. There are additional aspects to consider, but in broad strokes that's why an incorrect password will take longer to be rejected than a correct one will be accepted.",
"This is a technique called “tarpitting”. It slows down failed attempts to make brute force hacking harder. Brute force hacking can be very effective. But by its nature it has to try a lot of variants of user and password. Image for a second that this tarpitting never happened. It could blaze thru attempts until it found the name of your first childhood pet followed by an eclaimation mark. Considering It’s no big deal to perform hundreds of thousands of attempts per second (all depending on hardware) it’s only a matter of TIME before its cracked. Now if you slow it down painfully so it take a few seconds, it’s a minor inconvenience to a real human, but makes it almost impossible for brute force attacks. All that being said, even with tarpitting, it’s only a matter of time. Pick good passwords mkay?"
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[
"url"
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|
hhyk0s
|
why is it so hard for a PC to emulate a console like a PS4 or xb1 , even if though it has more CPU processing and GPU processing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"fwd12bj"
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"text": [
"Your computer can only count with Apples and the Xbox counts with lemons. The game code has the Xbox performing millions of calculations each second. When you want to run an Xbox game on a PC, the emulator pretends to be an Xbox and lies to the game you’re emulating. The PC is totally in on it though. When the game asks the fake Xbox (the PC) to multiply 3 lemons by 5, the emulator has to make the lemons look like apples and pass the fake apples to the PC that does the calculation. The fake Xbox then gets the result in apples back from the PC and makes them look like lemons and gives them back to the Xbox game. This conversion takes time so you need more processing power for the game to run at a normal speed. Sometimes the fake Xbox forgets what a lemon looks like and gives the game code an orange back and it crashes. Is that a good eli5?",
"Because not only you have to emulate the game but the whole system underneath, which is developed for another hardware that is not yours. So the challenges are mainly two: The first is the mere computational power that you need to emulate the entire operating system. Second you cannot simply install this system you have to do reverse-engineering on the existing one, which gets much more complicated as times pass",
"So let's say you have a Minecraft Redstone map and you try to run it on your PC. It will take some time for the circuit to work even if your PC is fast, because everything has to be done *in minecraft*, since your program only runs in Minecraft. The computer doesn't do the calculations directly, but has to simulate Minecraft's physics, in which the calculations are then done. Now think of the console as a native Minecraft world in which the behavior of Redstone is just how physics works.",
"Imagine your PC speaks Englsih but the cosole speaks Swahili. Your pc normally gets instructions in English and can do witrh them realy fast. However it doen't even know what to do with the xbox instructions. You need to run another piece of software, the emulator which takes the instructions an xbox game is sending and translates them into English. Your pc does what the instructions say and hands it back to the emulator which translates them into swahili and sends them to the xbox. The translations step is quite time consuming so you need much faster hardware than normal to do it in real time.",
"So it's not just a matter of having increased speed/resources. Game consoles have specific chip/circuit/hardware architecture which the PC needs to emulate as well in order for the game's software to work properly. Say I am visiting you and offer to make you dinner, it's my favorite recipe BUT I'm blind and I've never used your kitchen before to boot. In MY kitchen, the pasta is kept on the top shelf of the cupboard, the knives are to the left of sink, and the stove is to the right of the refrigerator, etc. I start cooking but when I go to get the pasta I can't find it in your kitchen, then have to search through the cupboard to find it, next figure out where to get a pot for the water, get a knife for the sausage, etc. The end result is the same delicious meal that you would have eaten at my house, but I had to do a lot of extra work and effort to cook it for you at your place."
],
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[
"url"
] |
[
"url"
] |
|
hhzu2p
|
How can a huge game like Skyrim fit on a CD and be played on a console, while only a few episodes of a TV show can fit on a DVD?
|
I know that there are two different machines used to read the disks, but does that make a difference in how much a single disk can hold? Is the difference in the way the disks are read or the type of data they hold?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Video games use text based code which is relatively small that references 3D models, textures, music and sounds that can be repeated thousands of times in the span of a game but only exist in one instance on the disc. A DVD uses about 30 individual pictures for every second of video and the sounds file is one giant movie-long piece of data. Nothing is repeated or reused.",
"A movie is like a cake and the DVD player is a fork you can eat it with. A game is like the ingredients and a recipe, and the computer is the tools you make the cake with and eat. The Skyrim files contain everything the game can show you (the textures, the models, the sounds, the voices) and has a lot of \"script\" to direct what goes where and what does what, but your computer (in this, a console is a computer) will do the work of reading the script and arranging everything according to it. Another analogy would be a record of a theater play and the play's text + costume descriptions. The recording is static, consumes a lot of place, but text is very small and costume descriptions even with pictures won't take a lot of space either. But then if you want to see the play, you have to manufacture the costumes and employ people to play the roles, which is what your console is there for.",
"Skyrim came on a DVD, not a CD. So in both cases it's the same amount of storage. A game like Skyrim is made up of lots of repeated data. There are loads of dungeons in it but if you look around the dungeons are mostly made up of the same models and textures repeated lots of times. So it doesn't need unique copies of that data for every single place it appears in the game (although it may be duplicated a few times for performance reasons). You can't do that with video. Video is compressed in various ways, including only storing the changes from one frame to the next instead of the whole thing. So In a way it can also reuse data to some extent. But if one episode of a show reuses a set from a previous episode there's no way to reuse the same bit of data for both episodes. We can easily tell it's the same scenery, but as far as the DVD player is concerned it's completely separate. It has no knowledge of what's in the scene, it's just looking at pixel values.",
"These are completely different things. The game is a program, and the program can calculate a complex scene from a few parameters. The TV show is a stream of data. There is no algorithm for calculating the next frame based on the last frame. Every frame can be optimized, for the part that doesn't change, but it's hugely data intensive. If you have HD, that's 1024x1980 pixels at maybe as few as 8 bits of 3 colors. Let's round it to 5Mbytes per frame at 30 frames per second. It eats up storage space, even with 20:1 compression."
],
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7,
5,
4
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|
[
"url"
] |
[
"url"
] |
hi8j4k
|
Why does it take so long for Bluetooth devices to recognize each other during setup?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwet8ag",
"fwen72d",
"fweqxom"
],
"text": [
"Bluetooth operates in the unlicensed 2.4Ghz spectrum. Each bluetooth pairing has it's own encryption setup During setup, the bluetooth host has to go through the entire spectrum and find out what is a usable bluetooth signal, and not someone else's encrypted connection or any other signal on the same bands like WIFI. Kinda like tuning each station on a TV one by one. Then if the new connection is usable and permitted, then there is a lengthy handshake process, and often the host has to install and configure drivers to make the connection usable. Lastly, for the average user, it's something that's done like once a year. It's not worth the cost and time to save a few seconds when it already cannot be instant. See here: URL_0",
"I can't get over the fact that devices that are physically close have more trouble setting up than devices connected through the internet.",
"I'd happy just knowing how I can be down by the pool with my phone and speaker and the speaker will immediately connect to every device my wife has ever owned sitting in the furthest corner at the opposite side of the house. :/"
],
"score": [
44,
6,
3
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"text_urls": [
[
"https://xkcd.com/1205/"
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|
[
"url"
] |
[
"url"
] |
|
hiaqpu
|
How do fitness tracking devices/smart watches analyze your sleep?
|
I recently got myself a smart watch and it has this feature that analyzes my sleep. Now I'm really curious on how it works. How can this thing that just kind of loosely sits on my wrist detect if i'm sleeping and why does it only need a sensor on the top side of the wrist? Afaik the top of the wrist isn't one of the usual spots to check a person's pulse.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwf8fr2"
],
"text": [
"Mainly by movement, in combination with heart rate, and sometimes apps on your phone that may pick up sound of snoring or slow breathing. Even if you've been still for a time (say, sitting reading a book, watching TV, lying in bed thinking) you *still* move somewhat (especially you limbs), and your heart rate is also higher than if you were asleep. The manufacturers know this, so they program the logic into their devices and the apps that go with them. They can *reasonably* determine if you're just lying back daydreaming, or actually asleep., logic assumes that you're asleep. As far as how it detects things while sitting *on top* of your wrist: it uses a red wavelength of light that peers *through your skin* and detects the \"redness\" and shade changes of your small blood vessels. From this, and due to lots of studies and analysis from actual medical equipment that does the same thing, we can guess with pretty good precision what your heart rate (and sometimes even oxygen level in your blood!) is."
],
"score": [
5
],
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|
[
"url"
] |
[
"url"
] |
hibspg
|
how the gaming console fan(s) collect dust while their are spinning rapidly all the time?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwf7nw1"
],
"text": [
"well static electricity what causes shocks when we touch someone or a door handle is present when two rough objects touch and it increases potency the faster the friction is. well the fans spins at high speeds the air friction and friction at contacts generate a electrical charge. Basically static electricity on the fans will attract dust and as time goes that dust start to stick more and more and depending on how moist the air is (humidity) it can even clump together into a solid mass."
],
"score": [
9
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hic4fe
|
Social media profiles are used to send targeted ads. What else can be done to us users with this data and how dangerous can it get?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwfcjqc",
"fwfi0xk"
],
"text": [
"Look up China's new system of rating people if you want to see the dangers. It's a real dystopian nightmare. If you say stuff that's critical of the state on social media, you lose points and that loses you privileges. For pictures you post on social media, some formats allow people to scrape your location from them. Post one pic about \"chilling at home with the fam\" and BAM, your home address is out there for the world to see. Post a few more, and a dedicated stalker can put together a pretty accurate depiction of your day to day life. And that's just a few examples.",
"Not just ads but targeted information. Two people with different beliefs and backgrounds perform the exact same google search can result in radically different search results. There is an example story of this happening in Egypt during the revolution, but more generally the implications are pretty grim."
],
"score": [
17,
4
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
higqyp
|
How is wood made into long & wide planks?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwg2wym"
],
"text": [
"Like plywood? Made by shaving a trunk in a continuous spiral then steaming it, flattening it out and gluing layers to desired thickness. If not plywood, you pretty much need a tree as big as you want the wood long/wide."
],
"score": [
15
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
hik4lv
|
Why are some microscopic images in colour while others appear in a sort of greyscale?
|
Is it purely a matter of differences in technology or is there a reason for this?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwgkzvp"
],
"text": [
"Images taken from light microscopes have color at lower magnifications. At higher magnifications, a thinner specimen is required in order to make out the necessary level of detail. Because the specimen is so thin, it can't filter light very much, so it doesn't display much color. Electron microscopes, on the other hand, aren't capable of detecting color. They don't make images from picking up light, instead they shoot electrons at the specimen and create an image from the reflected electrons. Sometimes, electron microscope images are digitally colored after the fact, but the actual picture that the microscope generates is greyscale."
],
"score": [
6
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
himjwe
|
How do doctors/surgeons fix bullet wounds when these hit organs?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwh3wjw"
],
"text": [
"It really depends on the organ that is hit, and the degree that it is damaged. With the liver, the main problem is bleeding. Controlling that can be with pressure and agents that promote clotting, suturing (actually not an easy thing to do with the liver), or sometimes taking out part of it. Other organs, such as intestines, might have the part hit removed or the hole sutured shut for minor injuries. As part of the surgery, the wounds, both inside and out, are washed with large amounts of saline to prevent infections. Side note-we don't really go searching for the bullet. If we find it, fine. But making sure to get it out really has little to do with saving the person's life despite what movies make it seem like."
],
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7
],
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|
[
"url"
] |
[
"url"
] |
|
hinh0h
|
How do braces work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwha88z",
"fwh2v5y",
"fwh2zpi"
],
"text": [
"Say you want all your first graders in a line facing the same direction to take a picture but they’re all jagged and crooked. To correct this, you strap on a backpack to each kid and feed a metal stiff cable through them to eventually mold them to face the right direction cause that cable is going want to straighten up. Once they’re corrected, you’re going to take out the cable and take off the backpacks, but eventually they’ll go back to being crooked because.. kids. That’s why you must wear a retainer every night. I don’t have a metaphor for the retainer bit",
"Braces on your teeth apply a force on your teeth which can gradually move them into more desirable places. Braces on your legs provide support to them that constrain their motion to avoid undesirable situations, typically while you are healing from an injury.",
"The teeth get little prongs glued to them. The dentist puts a wire through these prongs. The wires pull the teeth into the desired position. Making them straight. Every 2-3 weeks the dentist has to readjust the leverage of the wire, usually making it tighter so the teeth can be pulled further."
],
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6,
4,
3
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|
[
"url"
] |
[
"url"
] |
|
hioa3k
|
How do we ensure that so many phone numbers across so many carriers across so many regions each remain unique?
|
And have there ever been instances of duplicate numbers?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwh7m5v",
"fwh94mg"
],
"text": [
"No, duplicate numbers are not allowed. Each dialing area (what you probably call \"country code\", like +44, in an international phone number) has an organization responsible for coordinating the relationship between numbers and carriers. In the NANP (+1) this is the North American Numbering Plan Administrator (NANPA) which administers the North American Numbering Plan (NANP). They've divided this work up among several Local Number Portability Administrators (LNPAs).",
"I used to do this for work, keep in mind this information is for 10 number north America numbers. Basically when I am setting up your account I get your address. Using your address I look up your area code. An area code is the first 3 numbers and is associated with a particular geographic area. From there it is narrowed down to a particular exchange. An exchange is a local routing hub where all the land lines and cell numbers get together. Then we get to the last four digits. The last four are unique to each exchange and a customer can pick any available number from a universal list. Once a number is picked it is reserved for 30 days during that time the number cannot be taken by another user or provider. After 30 days if the number has not been put into service it's returned to the pool. If the number is activated it is marked in use till your line is cancelled. When you cancel a line the number is put aside for 90 days so that a user can change their mind and to avoid a new user getting calls to the previous owner of a number."
],
"score": [
4,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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hiohzw
|
In a recording studio, why use studio quality headphones, when most people won't be using those to listen
|
Studio quality headphones give accurate representation of sound, but most people listening to the music won't be listening with that high quality, so they'll miss a lot, or it might sound quite different for them.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"fwh938x",
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"text": [
"Because you want the source recording to sound as good as possible. Many people use quality speakers or headphones. Any recording is only as good as the weakest component in the chain, so you start high and then if people want to have a degraded experience that's their choice, but you don't cater to the lowest common denominator because then there is no quality version of the thing you just spent a lot of time and money to create.",
"When recording/mixing, you want headphones or monitors (speakers) with a \"flat\" equalization. This means no bass boost or treble boost or ultra boost. You're trying to hear the unaltered recording, and then choose how to equalize. However, good audio engineers will use several qualities of speakers to hear the song from multiple devices (phone, computer speakers, heavy bass, etc.)",
"Musicians are interest in what is actually recorded, not what most consumers will hear. They have above-average interest in the music, at a level of detail more like the technophiles that buy really good headphones.",
"Actually, lots of studiis will have special crappy sounding reference speakers, sometimes even several sets of them. They will have mono speaker, bad sterei system, apple wired earpods... All those can and should be used to check your mixing - cis what sounds goid on big soeakers, might sound shitty on listenee side, youre right.",
"You can not use any consumer sound system either because every system have their own issues. But studio headphones will give you the best possible representation of the sound and therefore be more of an average between all the different consumer systems. It is also expected that a hifi enthusiast will have an equalizer to make their system and their installation sound more like the studio headphones. Or they might even own profesional equipment themselves."
],
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119,
31,
27,
13,
6
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|
[
"url"
] |
[
"url"
] |
hiqttn
|
Why is formatting my drive so much quicker comparing to regular delete files?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwho91n"
],
"text": [
"A \"quick format\" just wipes out and recreates the file allocation table. That's just a list of files and where they are on the disk. Quick format - Tossing your whole filing cabinet into the incinerator and buying a new one. Deleting all the files individually - Taking out every file folder in your cabinet and putting a new, blank label on it."
],
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7
],
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[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hivu7i
|
Why is it that when you turn a device off by disconnecting it from the power point instead of pressing the off button it gets damaged?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwijfep",
"fwirkyk"
],
"text": [
"Digital devices unexpectedly powered off may have been in the middle of writing some data to the disk. When the machine starts up again and attempts to read that (potentially very important) data it may find a garbled mess and be unable to function in some (potentially important) way.",
"It won't cause hardware damage but it might cause data to get corrupted or lost. The power button sends a signal which tells the device to save everything it's doing and *then* turn off."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hj2zv6
|
Before atomic time, how did watchmakers know how long to make a second last for?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwjwol0"
],
"text": [
"They basically knew that day to day sun is up at approximately same time (or stars appear on horizon at same time too every nighta). So for a classic 12 hour clock, they'd take a 12-to-1 gear to get to get hours, 60-to-1 gear to get minutes, and 60-to-1 gear for seconds. Then by trial and error tune the mechanism so that hourly gear would make two full turns sunrise to sunrize, or tune it to match a sundial."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hj3mrj
|
what happens when we delete a file, like where does it go or what happens to it ?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwjz7c8",
"fwjyk4t"
],
"text": [
"Usually if you just delete a file conventionally you just say to OS that that space is free to rewrite/use in the future. File can be recovered until it is overwritten by a new data. There are more secure ways to delete a file - just overwriting it with random 0s and 1s on top of saying to OS that the space is empty and can be used freely.",
"The location on the storage device where the data for the file was is marked as free, and the reference to that location in whatever folder the file was in is removed. Future files are now free to overwrite that space. If the file is sensitive, like having cryptographic information, the deleting program may choose to also write random data to wherever the file was located before marking that location as free."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hj74ov
|
Why can't windows uninstall more than one application at a time?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwkhc3f"
],
"text": [
"Windows absolutely can, but the software is told not to. This is so two unrelated programs don’t mess with each other’s settings or try to modify the same files at the same time. Since you can’t control every other companies in the worlds software, it’s easier to just tell other applications they have to wait."
],
"score": [
13
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjclaq
|
- How does a bug happen in programming and how do people debug it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwldp41",
"fwldifj",
"fwldjd1",
"fwldo1r",
"fwmgiqd"
],
"text": [
"Somewhere in the programming there is a mistake - it could be something like a simple line of code saying that 1+1= 3, that would make every answer that uses that little bit of code would be wrong. Did you know that the term for a \"bug\" was because real bugs would get inside the original computers and get fried by one of the circuits! That was real fun trying to find a dead fly somewhere in a computer the size of your school gym.",
"Bugs happen when the programmer doesn't account for some edge case. A fairly easy to understand bug is an (integer) division by 0 (ie: if you write some code that read a number from somewhere and this number happens to be 0 it'll crash the program). Bugs are investigated using a debugger. A debugger is a tool that can run the program instruction by instruction and display the state of variables. In the case of a division by 0, the programmer might start his/her program in a debugger, try to get it to crash, and once it is crashed look at which line triggered the bug and at the state of all the variables used by that specific line).",
"There's many many lines of code in a given application. Bugs happen because of bad code. You could think of it like plumbing. The computer follows line by line what the programmer wrote. But, say on line 3, the computer was supposed to generate a number. But on line 1057 a line of code that needs that number to be in a specific format is written. When that line was written, no one knew to go back and change line 3 to make sure it formatted it correctly during generation. That's one way a but can happen. There's just too much happening for anyone to be able to catch every mistake. They are debugged though investigation and having tools like a debugger \"step through\" the code manually so that it executes line by line, but doesn't move forward until you tell it to, so you can inspect memory and make sure everything is the way you expect it to be. Once the bug is found, a fix is implemented and that goes into testing (to make sure the fix doesn't break other things) and scheduled for the next deployment",
"There are multiple ways there can be a bug in programming. Essentially, they're breaks in logic. Unlike humans when something doesn't make sense the computer can't recognize it, as far as it knows it is functioning as intended. In reality, the \"bug\" has caused the desired results to be skewed or the program to shut down entirely because it can't get past the bug.",
"The generic definition of software bug is this: Anytime a piece of software does NOT do what someone EXPECTS it to do. So a bug is not necessarily a mistake, it is just software not behaving to expectations. This definition broadens the concept of a bug beyond what most people think of when you say bug. Just thought I would put that out there. So for example, if the business person who paid for a data entry screen to be developed looked at the screen and said (the color of the name field should be BLUE not YELLOW) then that is a bug because the software has in some way not lived up to to the customer's expectation. Most bugs arise from some form of misunderstanding between the person who asked for a piece of software to be made, and the people who made it. Ambiguity, stupidity, and laziness are the three most common reasons for this. As you can see, bugs in software are 99% the result of people just being people. I will also say that contrary to below posts, at least half of all bugs are NOT the result of a programmer making a mistake, but rather from ambiguity in the original request. The most common method of debugging is decomposition and reconstruction. In this method we work from the inside out, checking a very small piece of code and making sure it is correct. We then work outwards adding more pieces of code that use the now validated smaller piece of code, until we find an error. We know that any error found is most likely in the new piece of code just added since the prior pieces of code all tested out OK. After we fix the wrong code so that it works we test the original full code and if that works too we likely will call the problem fixed and pass the new fixed code on for others to use."
],
"score": [
11,
6,
6,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjfdfg
|
Why YouTube has stopped considering 720p as HD quality?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwluccp"
],
"text": [
"It doesn't matter. YouTube probably just assumed given that many customers' displays can natively support resolution above that, and that most content uploaders are uploading at least 1080p these days, that the \"HD\" designation over 720p makes no sense."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjjwy6
|
How the data in a computer is processed differently by each component (hard drive, RAM, CPU, graphics card, etc.)
|
I guess I'm looking for like where the data travels between each component (ie: file is stored on a hard drive, user opens file and it gets moved to RAM, the CPU is running processing it all, etc). What does each component actually do when it's processing the data? I'm especially wondering about what a graphics card does that the CPU doesn't and vice versa.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwmqj9t"
],
"text": [
"Graphics card processes a lot of easy math problems fast. This is why it can do math for each pixel sixty or more times per second. Cpus are extremely fast calculators and can do hard long problems quickly. When it opens a program, it’s doing tons of math to put the program in place. Ram is fast and can keep track of a good bit of info at once. It’s volatile, so it relies on electricity. It will lose everything in a power outage, but the electricity helps it go extra fast. A hard drive uses little bits of metal and magnetized them in different directions. The hard drive is still fast these days, but can not compare to ram. A operating system has a schedule. Tasks that need to be done now are given to the cpu to do. If they need to access information, that information is retained for use with ram. If there’s multiple tasks going on, the ones that aren’t getting progress will try to stay in ram. If you have a lot on your computer, ram can fill up and it’ll push some info to the hard drive. If you push things to the hard drive, you can actually notice the slowness in response times because the hard drive is slower. Hard drives are slow because they need to be able to permanently store data for a lot of usage. They are constantly used and plugged in and the information on them should not be lost"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hjlqsf
|
. Why can’t robots be programmed to click a box that says “I am not a robot”?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwn1sms",
"fwn4gcl"
],
"text": [
"The button checks the micro movements of your mouse to see if it's predictable like a robot or random like a human. That being said, robots can defeat all types of captchas with reasonable accuracy, but defeating the ones that make you click on images of stop signs takes more expertise and is a higher barrier of entry for would be spammers.",
"The clicking of the box is not the test but a way that you can trigger an image captcha if needed. The test includes how you move your mouse and how fast you click it but the real test is what you have done on the web before. Google tracks you in large part to serve advertisement so it looks at what that browser has done before. It also looks at what you have done on that website or your IP have done so stop multiple automatic operations. So it is that total behavior of all google knows about you that is relevant for the determination. Often the test is hidden so the button might only appear if the code suspects you. If Google is not sure they throw up an imager recognition problem for you to do."
],
"score": [
45,
11
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjoljc
|
How does YouTube handle different frame rates? Ex US: 30fps or 60fps vs Europe's: 25fps or 50fps? How are they effectively removing judder from a video filmed in PAL and me watching on an NTSC set? Does it scale by Geographic location? So many questions about this.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwo04js",
"fwnsz5l"
],
"text": [
"Youtube doesn't transmit over PAL or NTSC. Those are obsolete cable TV standards. Youtube transmits video over the internet. Every modern computer display can do at least 60FPS regardless of continent.",
"Do the old formats even exist anymore? PAL was an over the air standard."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjs1jk
|
Why are there ebooks that are checked out, and therefore unavailable? Since it is online, couldn't the ebook just be copied and pasted so that the people who want to read the book but are unable to because someone else is reading it don't have to wait for them to finish?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwo68dj",
"fwo77p3",
"fwor74s",
"fwog29v",
"fwods0y",
"fworfkg",
"fwpg806",
"fwp0aei"
],
"text": [
"There is an old rule about if you own something you can lend it to someone but it has to stay just that one copy. This doesn't violate any sort of copyright. So in the modern age, a library has to buy say 3 copies of whatever Stephen Kings new novel is in a PDF format and can lend up to 3 copies in that format out at a time and avoid legal trouble.",
"If you borrow through a library's ebook service, they only have bought the rights for a certain amount of copies of the book, and while ebooks are cheaper and the library may have more, they still only have a limited number and can only \"lend\" the amount they have.",
"Hey, something I know about - I used to sell eBooks to clinical and academic libraries. Most eBooks provided by libraries are part of the old mode of licensing, where the library buys based on user access. The most common are one book one user (or 1B1U ie. one copy available), 1B3U (three copies) and 1BUU (unlimited users), the latter being more expensive. Most libraries will be buying one of these versions. There are now different models available that are more user friendly. Demand-driven Acquisition (DDA) allows the library to display a large range of eBooks, only having to pay for access when a user triggers a purchase by reading 10 pages, printing or downloading it. This gives a lot of libraries the willies, as it removes a degree of control over budget. There are also big collections of eBooks that can be purchased by libraries on an annual basis that give good access levels. These are also a bit iffy for some libraries, as the ongoing cost can overtake the value of the collection after a few years depending on the quality of the titles included.",
"Because otherwise whenever a new book is published you could have a world library thst just buys one copy then 'loans' it to millions of people around the earth all at the same time Seems fairly sensible for publishers to make a rule that you can only symultaneously loan as many books as you have bought. Exactly how it is with physical copies of books",
"It’s to keep things fair for both parties, the owner have limited ownership to his copies just like physical book while the author’s copyright is protected.",
"You don't need to copy an ebook. When you get an ebook from the library you're essentially getting a temporary license that gets installed on the device and you download a copy of the ebook. You could have infinite copies of the book to lend but the publishers don't want that. If they could get away with it, publishers would make libraries illegal, period. The limited number of ebooks available is probably a combination of financial reasons, since libraries need to pay for every license they purchase just like it was a physical book, and agreements with publishers who want to keep this number as low as possible.",
"And let’s not forget that unlimited copies of an ebook means the author of that book doesn’t get paid for everyone that reads it. It’s one of the reasons libraries pay more for books than regular readers.",
"Hey, and oddly niche topic my somewhat niche job applies to! I'm a software developer at a company that sells books and distributes a reading app for digital resources. The gist is that every publisher will work out licenses for their resources because naturally they're a business and want to make money. As far as digital resources go, they make their money by selling licenses to book distributors. We may be allowed to distribute their resources in one of several ways based on the exact license. A common license is that only one user is allowed to check out a digital copy of a book for each school/library purchased copy. But there are also other licenses that allow, for example, unlimited checked out copies. And then there are even more restrictive but even cheaper licenses that are basically single-use copies: the book is only allowed to be distributed out once and is only valid for, say, 60 days before it's no longer allowed to be read, but then it only costs, say, $1 a book from the publisher. The idea for these, generally, is to be bought in bulk for class assignments and distributed to students of the class. tl;dr: Publishers dictate the terms of licenses (i.e. how people checkout ebooks) so that they can do business."
],
"score": [
211,
55,
15,
9,
5,
4,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjtox0
|
How do phones keep track of time when they are out of battery?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwoetqz",
"fwojrw9"
],
"text": [
"When phones shut off they aren’t actually out of battery, they go to sleep to prevent battery damage so the clock of kept running. If the battery truly dies, then it gets the time from the phone provider when it sets itself so you never really notice it.",
"Your phone reads the time from the cell tower directly. This was easily observed during air travel, when you still had to turn off your phone. When turning your phone back on upon arrival the phone displayed the time in your original timezone as it searched for a cell tower. Moments later the time updates to local time. While technically, it is possible for this to be done from the global positioning system, in practice it's not. * You don't have to go back too far to find phones that didn't support GPS. * GPS is more battery intensive than reading it from the cell tower * GPS is based on UTC time which would require resolving your coordinates to the timezone to apply the UTC to local conversion. This is more complicated than it sounds as there is high variability in the application of time zones globally. * It's already part of the cell communication signal, so no further work is required. URL_0 Edit: added a link"
],
"score": [
13,
4
],
"text_urls": [
[],
[
"https://blog.american-time.com/the-sync-options-for-a-master-clock"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjtskn
|
. How does a PDF compressor work? How does it give the same quality, with lower size?
|
I compressed a PDF file that was around 95 MB, and the online compressor compressed it to only 1.15 MB, but when I viewed the file it still has a great, almost exact same quality.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwogfrn",
"fwolbnk"
],
"text": [
"PDF are technically not \"an image\", but rather text, special text, \"code\". A lot of that can be considered \"clutter\", often left behind for redundancy or for being inefficient. Compressors usually de-clutter the file, then applies actual compression (which Tom Scott made an excellent video about on youtube, I recommend checking it out.) In short: Trims the excess useless fat, then applies regular compression.",
"The word file means a folder for something. A PDF file is a folder for stuff.. One of those stuff is the document - the collection of images, words that you read on the screen. There are usually other stuff, such as notes uncle Bob (bob.exe) left when he made some changes. Do you remember Aunt Mary? She talked quite a lot and wasn't good at documenting things so she always added extra details than necessary. Whenever someone makes changes, a little bit of extra stuff gets added. A PDF compressor comes in and says yo guys, we don't need uncle bob or mary to be in this shit anymore. It's been a long time, let's remove that stuff but leave the main images and words intact! Those are important."
],
"score": [
22,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
hju5pj
|
Why is that when you photograph a television or phone screen, the picture shows squiggly lines all over the screen?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwok8hz",
"fwohuxu"
],
"text": [
"You might be seeing something called a moire pattern - it's caused by two grids (in this case, the tv pixels and the camera pixels) being slightly different scales.",
"It is more down to the human eye than the camera. Most people cannot really detect flickering above 40hz, a certain percentage can perceive above 60hz and some crazy people with training can see much higher (like over 150). Most screens (TVs and pc screens) are 60hz refresh rate so when we look at them we see a smooth picture. Now we if there was a missing frame 1/60 we could probably see it or notice it at least. What we don’t notice is that screens refresh from left to right and even older ones refresh left to right, line by line from bottom to top. So basically when you take a picture it is a snapshot of the screen refreshing itself and so certain parts of the screen are showing a slightly different picture, which makes things appear out of line. The camera picks up what we generally cannot. Edit: I should say for modern LED screens the pixels refresh all at the same time. However they will be ever so slightly out of sync due to manufacturing Torrance’s etc. The same thing as above applies though. What we see and what the camera picks up on is slightly different."
],
"score": [
15,
12
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjubub
|
How come, with new technologies, the quality of calls doesn't improve ?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwokug3"
],
"text": [
"Because there is already a widely accepted algorithm implemented, that can't be changed this easily as it possibly isn't compatible to newer systems without extra measures in end-to-end signal processing. In the USA this algorithm is the [µ-law algorithm]( URL_0 ) that compresses signals depending to their amplitude with respect to human hearing in differently scaled loudness-steps, where quiet signals are quantisized with more precision than loud signals. The main benefit of that algorithm is that it compresses a signal of e.g. 14 Bit per sample to 8 bit per sample without subjective loss of quality. This is critical for transmission channels of limited bandwidth, such as landlines that used analogue transmission methods until 1990-ish. Today Voice over IP is totally a thing that improves quality theoretically indefinetely, but the quality of telephone calls is pretty much set."
],
"score": [
8
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/%CE%9C-law_algorithm"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
hjvupa
|
How is single-stream recycling processed?
|
I grew up with separating recyclables and putting them in different bins at the recycling center. Now we can put everything into a single bin. How is it separated for processing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwox37r"
],
"text": [
"Basically it goes to a sorting plant that filters things based on: Magnetism/Eddy current to remove metals. Water and air current to sort heavy plastic and paper products from light ones. Augurs and paddles to sort scraps from full-size items. Plus there are usually one or two human sorting stages where people throw things into various bins."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
hk42aw
|
why does a guitar pedal need a battery or an adapter when it's already getting power from an amp?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwqdwlq",
"fwqgz88"
],
"text": [
"Yeah, thats not how that works. An electric guitar doesn't get power from the amp. The electric guitar is generating very very small electrical signals by the strings moving over the magnets of the pickups. These signals go through the cord to the amp which _amplifies the poop out of them._ So unless the guitar pedal is passive and only works on the signal magnitudes as they come from the guitar, it needs some external power.",
"I might add: some microphones are powered externally, by the mixer or amp. This is called “phantom power.” However, amps don’t power guitars or pedals, as far as I know. Those require external power."
],
"score": [
16,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
hk50of
|
How does a camera save what it captures?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fwquj3k"
],
"text": [
"Depends on the technology in the camera. If its a film camera, the light is focused on a strip of chemicals which are effectively 'burnt' by it and so capture the image. A digital camera focuses that light onto a grid of photosensitive sensors, much like our eyes, and it records the data it gets from them."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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