How computers work
What makes a computer, a computer?
(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.