this is termed as Input-Processing-Output cycle. A computer receives data as input, processes it, stores it and then produces output.


The working of a computer is shown in the following figure:

It functions in the following manner:

Input

Computer input is whatever is entered or fed into a computer system. Input can be supplied by a person (such as by using a keyboard) or by another computer or device (such as a diskette or CD-ROM). Some examples of input include the words and symbols in a document, numbers for a calculation, instructions for completing a process, pictures, and so on.

Processing

The computer perform useful operations by manipulating the data in many ways. this manipulation is called processing. Examples of processing include performing calculations, sorting lists of words or numbers, modifying documents and pictures according to user instructions, and drawing graphs. A computer processes data in the CPU.

Storing

The computer stores data. A computer must store data so that it is available for processing. Most computers have more than one location for storing data (the hard drive or C:\, and the floppy drive or A:\). The computer puts the data in one place while it is waiting to be processed and another place when it is not needed for immediate processing.

Output

The computer produces output. computer output is information that has been generated by a computer. Some examples of computer output include reports, documents, music, graphs, and pictures. Output can be in several different formats, such as paper, diskette, or on screen.