A computer is a machine that lets you store information: words, numbers, sounds and pictures. It allows you to see on its screen what you have stored. It can be made to change the information you have typed into it. It can do arithmetic, like a calculator. It can collect information from other people too. The computer can be used to send messages to people, like posting a letter, but the person getting the letter will just read it on their computer. Because lots of people can use their computer to write information, the information can be stored in big machines called "servers". This means that you can use a computer to ask questions and find out what things other people have written about, like going and looking in books in a library.
