What is a Computer?

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A computer is a programmable machine that performs high-speed processing of numbers, as well as of text, graphics, symbols, and sound. Modern computers are digital. The computer's physical components are called hardware; its programs and data are called software. All computers include these components: central processing unit, referred to as the CPU, that interprets and executes instructions.
•input devices, usually a keyboard and/or a mouse, through which data and commands enter the computer.
•memory that enables a computer to store programs and data.
•mass storage devices, such as disk drives and tape drives, that store large amounts of data; and

•Output devices, such as printers and display screens, that show the results after data has been processed by the computer.

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