A computer is a machine that is able to take information (input), do some work on or make changes to the information, to make new information (output). Computers have existed for much of human history. Examples of early computers are the astrolabe and the abacus.
Modern computers are very different from early computers. They are now very powerful machines that are able to do billions of calculations every second. Most people have used a personal computer in their home or at work. Computers are useful for many differentjobs where automatic tasks are useful. Some examples are controlling traffic lights, vehicle computers, security systems, Washing machines and Digital Televisions.
