Computers are electronic systems designed to manipulate data through four basic functions: input, processing, storage, and output. Programs are sequences of instructions that control how the computer performs operational functions. Computers can be classified by purpose as general-purpose, which can handle a variety of problems, or special-purpose, designed for a specific task. They can also be classified by the type of data handled as analog, digital, or hybrid.

1. Computer Systems HardwareLesson 6

2. The ComputerAn electronic system designed to manipulate data . They are machines for storing , moving, adding, and subtracting, and evaluating data.

3. Four Basic Functions of ComputerInputProcessingStorageOutput

4. ProgramSequences of instructionsThese instructions control the manner in which the computer carries out its operational functions.A computer will perform only what it is

5. Classification of Computers by PurposeGeneral-Purpose ComputerThese machines have the capability of dealing with a variety of different problems , and are able to act in response to progress created to meet different needs.It has the ability to store different programs of instruction and thus to perform a variety of operations.

6. Classification of Computers by PurposeSpecial – Purpose ComputerIt is designed to perform one specific task.They are referred to as dedicated.

7. Classification of Computers by type of data handledAnalog Computers are used for scientific , engineering and process-control purposes.It provides an analog or simulation of the object or system it represents.Digital ComputersIt is a machine that specializes in counting.

8. Classification of Computers by type of data handledHybrid ComputersCombines the measuring capabilities of the analog computer and the logical and control capabilities of the digital computer.It offers an efficient and economical method of working out special types of problems in science and various areas of engineering.