In general, and simply put, a computer is a machine that performs a series of mathematical calculations or logic operations automatically. Computer specialists often divide computers into two types: An analog computer operates on continuously varying data; a digital computer performs operations on discrete data.

The majority of today’s computers easily process information much faster than any human. The response (output) of a computer depends on the data (input) of the user, usually controlled by a computer program. A computer also can perform a large number of complex operations, and can process, store, and retrieve data without human interference.

There is a great deal of overlap for the word “computer.” In a more archaic sense, a computer is called an electronic computer, or computing machine or device; the more common expressions include data processors or information processing systems. But remember, there is a definite difference between a computer and a calculating machine: a computer is able to store a computer program that allows the machine to repeat operations and make logic decisions.