What are the 4 main components of a computer system?

A computer system is built up of components such as Hardware, software, programs, data, and networking. Without these components, no system can run.

In addition to these elements, a computer system consists of four major components. And they are: central processing unit, input/output devices and Memory as shown in figure below:

components of a computer system
Fig. components of a computer system

Here, Input devices send data to the processor, which processes it according to the predefined instructions and produces useful results/information for the user through output devices. Along with this, the information is saved in the computer’s memory as well.

Let’s take a closer look at them.

Major components of a Computer System

Input Device

Input is any data or instruction that a computer collects from the outside world. The input can be in the form of text, programs, commands, and user responses.

The device that collects the input and sends it to the computer is called an input device. Input devices include the keyboard, mouse, scanners, digital cameras, nicrophone, etc.

Input Devices : Components of a computer system

The input device is used for entering data or instruction to the central processing unit. Some major functions of input devices are:

  • It accepts data from the user or outside the environment.
  • It converts user understandable form of data into binary code that is understandable to the computer.
  • It sends data & instructions in binary form to the computer for further processing.

Central Processing unit (CPU)

The central processing unit(CPU) is the main information processor in a digital computer capable of executing a program. The manipulation of the raw data based on the instruction is called processing.

 A computer processes data in a device called the central processing unit. It is a very complex integrated circuit, containing millions of miniaturized electronic components.

The CPU servers as a “brain” of the computer. The speed of the CPU is measured in Hertz(MHz, GHz, etc). The various types of CPU chips are intel Celeron, intel core i3, i5, i7, etc.

CPU: Main Components of a Computer System


 A computer has a huge data storage capacity. Storage is the place where data is held in an electromagnetic or optical form for access by a computer processor.

Storage has been divided into:

Primary Storage:

Primary storage holds data in memory. The primary storage (also known as main memory, internal memory, or prime memory), also known as memory, is the only one that is directly accessible to the CPU. e.g. Random Access Memory or RAM

The CPU constantly reads instructions from memory and executes them as needed.

8+ Free Dimm & Ram Photos - Pixabay
Main Memory (e.g. RAM): Components of a Computer System

Secondary Storage:

Secondary storage holds data on hard disks, tapes, and other devices requiring input-output operations. Secondary storage (also known as external memory or auxiliary storage) differs from primary storage where it is inaccessible to the CPU directly.

The computer’s input/output channels are typically used to access secondary storage and transfer data to primary storage.

Secondary storage are Non-volatile in nature. i.e. retaining data when its power is shut off.

Free photo: dvd, blank, data, computer, data medium, digital, disk | Hippopx
Secondary Memory : Components of a Computer System

Output device

The output device is any peripheral device that receives or displays output from a computer. Output is any computer-generated information displayed on-screen or printed on paper. It can be in the form of words, numbers, graphics, sound, videos, and animations.

Analogue, Digital, and Hybrid Computer
Screen : Components of a Computer System

An output device performs the following functions:

  • It accepts results produced by the computer in binary coded form and converts them into human acceptable form.
  • It supplies converted results to the display unit or outside world.

The monitor, printer, and graphic plotter are some of the popular output devices.

Output sent to a monitor is called softcopy while output sent to a printer is called hardcopy.

Learn about Computer System by Clicking Here

Or, Click here to Play Quiz based on Computer System
by Tech andro

Leave a Comment