Summary
Highlights
All computers perform four basic functions: input information, store and process information, and output information. Each function is handled by a different part of the computer.
Input devices convert information from the outside world into binary data for the computer. Examples include keyboards, touchpads, cameras, microphones, GPS, and sensors in cars, thermostats, or drones.
When a key is pressed, the keyboard converts the letter to a number, which is sent as binary to the computer. The CPU calculates how to display the letter pixel by pixel, requesting instructions from memory. The CPU runs these instructions, stores the results as pixels in memory, and then sends this pixel information in binary to the screen, an output device.
Output devices take a binary signal from the computer and perform an action in the physical world. Examples include screens, speakers (playing sound), 3D printers (printing objects), robotic arms, car motors, and milling machine cutting tools.
New types of inputs and outputs allow computers to interact with the world in new ways, aided by improvements in speed and size of memory and CPUs. More complex tasks and information require greater processing power and memory. Modern computers use multiple CPUs and gigabytes of memory for demanding tasks like 3D graphics or high-definition video.
Every action a computer performs involves inputting information from the physical world, storing and processing that information, and then outputting something back into the physical world.