A computer is like a really fast robot that does calculations. It has a brain, which is the Central Processing Unit or CPU. It has a memory, which remembers things. It has eyes, which are the input devices that tell it what to do. It has hands, which are the output devices like the keyboard, mouse, and monitor that it uses to show you the results of its calculations. It also has a voice or a speaker so it can talk to you when it's done. The computer follows instructions, so you have to tell it what to do by typing in commands or running special programs. To do this, you need to know a language called a coding language.