Data Entry: Basics of Computer: Introduction, Functions and Characteristics of Computer

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You would have observed that instructions have to be fed into the computer in a systematic order to perform a specific task. Computer components are divided into two major categories, namely, hardware and software. In this lesson, we will discuss about hardware, that is the machine itself and its connected devices such as monitor, keyboard, mouse etc., as well as software that makes use of hardware for performing various functions.

What is a Computer?

A computer is a machine that accepts data as input, processes that data using programs, and outputs the processed data. An electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.

Functions of Computer

  • It accepts data or instruction by way of input,

  • It stores data,

  • It can process data as required by the user,

  • It gives results in the form of output, and

  • It controls all operations inside a computer.


  • High Speed,

  • Accuracy,

  • Diligence,

  • Versatility,

  • Storage.

Image of Computer Characteristics

Image of Computer Characteristics

Computer Organisation

  • Input: this is the process of entering data and programs into the computer system.

  • Control Unit (CU): The process of input, output, processing and storage is performed under the supervision of a unit called 'Control Unit'. It decides when to start receiving data, when to stop it, where to store data, etc. It takes care of step -by-step processing of all operations inside the computer.

  • Memory Unit: Computer is used to store data and instructions.

  • Arithmetic Logic Unit (ALU): The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparison.

  • Output: This is the process of producing results from the data for getting useful information.

  • The ALU & CU of Computer are known as CPU the brain of computer.

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