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What makes a computer, a computer?

Inventor and designer May-Li Khoe and virtual reality designer Nat Brown introduce the four features that all computers share.

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  • female robot ada style avatar for user Katey Gordon
    We know from this video see the 4 functions could these 4 functions apply to the same way the brain works for example the 4 are
    Input -Study Environment, senses , emotions etc.
    Storage -Short Term Memory, Long Term Memory
    Processing- Thinking , Problem Solving and Developing
    Output- Through these functions we perform our actions given for example homeworks, build ,create or do something.

    Doesn't this means the computer is almost like a Brain and how it functions?
    (30 votes)
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    • blobby green style avatar for user omearad
      A computer is similar to a brain because a brain also receives, stores, processes and outputs information. However a brain has a conscience and thinks about how there output will effect themselves and others.
      (28 votes)
  • blobby green style avatar for user Michael Dvus Laudano
    is this portion of khan academy instructional videos only? i see no exercises
    (10 votes)
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  • blobby green style avatar for user Chinmay Gupta
    The 2nd task of all computers, as you mentioned was "storage", is that referring to the cache of the processors or actual bulk storage mediums? I would assume it would mean temporary storage areas, such as the cache, because that is where the input has to go before it gets processed. Let me know if my assumption is wrong. But then where in the cycle does the bulk storage area fit in? Would it also be part of the output category, since data can be inputted, stored in the cache, processed, and then outputted, into a file that lies on a drive (bulk storage device)? For example, rendering a video, since the output is saved onto the drive, would it be considered as output?
    (4 votes)
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    • male robot hal style avatar for user Cameron
      For computers, storage is just somewhere you can load data from and store data to.
      So storage would include cache memory, main memory, hard drives, tapes, and other methods of storage that haven't even been invented yet.

      The original concept of storage (back when computers were an idea and hadn't been built yet) was an infinitely long strip of tape that the read/write head could move back and forth on. To find out more about this device, called a Turing machine, check out: https://en.wikipedia.org/wiki/Turing_machine
      (9 votes)
  • blobby green style avatar for user billozero
    Can we have 'processing cycle' (timestamp ) that includes input, processing, storage and output, but also 'communication'? How would communication fit into the processing model? Is it the same as output or is it the result of output? And presumably communication in a network becomes input to other computers - or even feedback that becomes input to the computer that generated the output / communication in the first place?
    (2 votes)
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  • duskpin ultimate style avatar for user LilD3mon
    how can i make my own pc and how much is going to cost
    (3 votes)
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  • mr pants pink style avatar for user just another unicorn
    In some textbooks I've seen they said that storage and memory were two different things but in the video the man seemed to use it interchangeably. Are the two different?
    (1 vote)
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  • blobby green style avatar for user alexas.floyd
    How do these things do exactly what it needs to do?
    (3 votes)
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  • mr pants green style avatar for user riley smith
    so if you were to take apart a computer and take out th specific components could you like tranfer them to say like a toaster and put a screen on it could you make it a smart toaster
    (3 votes)
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  • hopper cool style avatar for user Moksha
    How can the input of one computer become the output for another (and vice versa)?
    (1 vote)
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    • leaf green style avatar for user Shane McGookey
      The process is relatively complex, but it should not be too difficult to understand the basics. Let us break it down, step by step:

      First, let us consider that you are running a chat application on your own computer. You open up a new chat with your friend, Jeremy. You want to say "hello" to Jeremy, and therefore you input "hello" using your keyboard. The computer reads "hello" as a string of characters, and therefore reads your message as 'h', 'e', 'l', 'l', 'o'. These characters are then converted to binary (0s and 1s) using ASCII encoding (you can search this term).

      Second, once the characters have been converted, they are sent across a network connection to Jeremy. This network connection can be through physical wires (Ethernet cables), WiFi, or otherwise. The message will be routed through various different devices on its way to Jeremy, unless of course you are directly connected to Jeremy's computer (e.g. you two are in the same household and are connected via a singular Ethernet cable).

      Third, Jeremy's computer will receive the binary encoding of "hello." Jeremy's computer will decode each letter of the message, and print each letter to Jeremy's screen in succession on the chat application. Therefore, "hello" will print onto Jeremy's screen via the chat application and he will then have the opportunity to respond.

      The complicated parts of this process are entailed in the sending of the message across the network that connects both you and Jeremy, and the conversion process that converts the message to binary. Other factors must be considered such as the endianness of the binary encodings and otherwise, but these can be left out as they are not necessary to understanding the basic process.
      (4 votes)
  • blobby green style avatar for user Otter20@
    Why is a computer made of so much parts??
    (2 votes)
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Video transcript

(upbeat music) - One, two, three, four! - My name is May-Li Khoe and I'm a designer and an inventor. So, some of the things I've designed have been at Apple, and now I design products for kids to use so that they can have an easier time in school. My other jobs include DJ'ing and dancing. (upbeat, bouncy music) Computers are everywhere. They're in people's pockets, they're in people's cars, people have them on their wrists, they might be in your backpack right now, but what makes a computer a computer? - What does make a computer a computer anyway? - And how does it even work? (upbeat guitar music) - Hi, I'm Nat. I was one of the original designers of the Xbox. I've been working with computers since I was, maybe, seven years old and now I work on virtual reality. (fast, jazzy music) As humans, we've always built tools to help us solve problems. Tools like a wheelbarrow, a hammer, or a printing press, or a tractor trailer. All of these inventions helped us with manual work. Over time, people began to wonder if a machine could be designed and built to help us with the thinking work we do. Like solving equations or tracking the stars in the sky. Rather than moving or manipulating physical things, like dirt and stone, these machines would need to be designed to manipulate information. - As the pioneers of computer science explored how to design a thinking machine, they realized that it had to perform four different tasks. It would need to take input, store information, process it, and then output the results. Now this might sound simple, but these four things are common to all computers. And that's what makes a computer a computer. - [Nat] The earliest computers were made out of wood and metal with mechanical levers and gears. By the 20th century though, computers started using electrical components. These early computers were really large and really slow. A computer the size of a room might take hours just to do a basic math problem. - [Announcer] These machines are things of gleaming, varied colored metal and numerous flashing lights. - Computers started out as basic calculators, which was already really awesome at the time and they were only manipulating numbers back then. But now we can use them to talk to each other, we can use them to play games, control robots, and do any crazy thing that you could probably imagine. - Modern computers look nothing like those clunky old machines, but they still do the same four things. (funky, upbeat music) - First, we're gonna talk about input. This is my favorite because what input is, is the stuff that the world does, or that you do that makes the computer do stuff. You can tell a computer what to do with the keyboard, you can tell them what to do with the mouse, the microphone, the camera, and now if you're wearing a computer on your wrist, it might listen to your heartbeat, or in your car it might be listening to what the car is doing. And a touchscreen can actually sense your finger and it takes that as input on what it's doing. - All these different inputs give the computer information, which is then stored in memory. A computer's processor takes information for memory, it manipulates it or changes it using algorithm, which is just a series of commands, and then it sends the process information back to be stored in memory again. This continues until the processed information is ready to be output. How a computer outputs information depends on what the computer is designed to do. A computer display can show texts, photos, videos, or interactive games, even virtual reality. The output of a computer may even include signals to control a robot. And when computers connect over the internet, the output from one computer becomes the input to another, and vice versa. - The computers we use today look really different from the earliest thinking machines. And who knows what the computers of tomorrow will be like. My hope is that you get to help decide what you want the computers of tomorrow to look like. But across all computers, regardless of the different types of technology they use, they're also doing the same four things. They take in information, they store it as data, they process it, and then they output the results.