Definition of Computer
Computer is an electronic device or machine which has the ability to accept data, process data and send out information as output. it has the ability to store and retrieve information.
A computer is a programmable machine, it allows the user to store all sorts of information and then process that information or data or carry out actions with the information, such as calculating numbers or organizing words.
Computer can be generally classified by size and power namely
(1) Mainframe Computer
(2) Super Computer
(3) Mini Computer
(4) Micro Computer.
Computer as an Input – Processing – Output (IPO)
Some of the parts of computer are responsible for accepting (input) data, some are for processing data while some are used for bringing out (output) the output from the computer after processing.
The three components or parts are regarded as Input – Processing – Output (IPO) system.
Components of a Computer
Computers are made up of Hardware and Software.
Hardware: The physical equipment required to create, use, manipulate and store electronic files.
Software: The computer instructions that operate a computer, manipulate the data and execute particular functions or tasks.
All computers required the following hardware components:
- Central Processing Unit (CPU): The chip or chips at the heart of a computer that enable it to process data. Also known as a processor.
- Memory: An area within a computer system that holds data waiting to be processed
- Storage Device: The place where a computer puts data.
- Input Devices: The devices that allow data and instructions to enter a computer (such as a keyboard, mouse, scanner)
- Output Devices: The devices that allow information to be given out to the users, such as a display screen or printer).
How Does A Computer Work?
- The computer accepts input: Computer input 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).
- The computer performs useful operations, manipulating the data in many ways. This manipulation is called processing. E.g. performing calculations, sorting lists of words or numbers, modifying documents and pictures according to user instructions.
- The computer stores data: A computer must store data so that it is available for processing. The storage of data in the computer is called online storage while the storage of data on computer tapes, diskettes or CD-ROMs is called offline storage.
- The computer produces output: Computer output is information that has been produced by a computer. E.g. reports, documents, music, graphs, pictures. Output can be in several different formats such paper, on screen, speaker, etc.
How Software Work
Software is the instructions that operate the computer, execute particular functions or tasks, and manipulate the data.
For Software to perform various functions, it must be programmed. Every Software executes it tasks according to how it was programmed to do. It tells the computer hardware how to execute tasks, when to execute them and when to execute those tasks.
Evaluation:
- What is a computer
- Explain the Input-Processing-Output system
- List Three Components of computer hardware