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Components of a Computer System



Components of Computer System

Computer systems have 4 main types of component:

  • Input Devices
  • Output Devices
  • Processing Devices
  • Storage Devices

Some devices may fall into more than one of the above categories.

Example a smartphone touchscreen is both an input and output device.

  • Input – the device senses where you touch the screen
  • Output – the device displays graphics and text on the screen.

IGCSE ICT Components of a computer system


Input Devices

Input devices are any devices that allow data to be input in to a system.

Input devices include:

  • Keyboard
  • Mice
  • Scanners
  • Barcode readers

components of a computer system input devices



Output Devices

Output devices are devices that give information out to the user.

Output devices include:

  • Monitor
  • Speakers
  • Printer

Components of a computer system output devices



Processing Devices

Processing devices are devices that perform calculations on inputs and sends data to output devices to output data to the user.

An example would be:

  • Input – User presses the space bar.
  • Processing – The computer processes the space bar as a signal for a computer game character to jump within a game. The computer calculates the new position of the game character
  • Output – The computer sends the new screen image to the screen in order to output the new position to the user.

Processing devices on a computer include:

  • The CPU
  • The GPU

Components of a Computer System Processing Devices


Storage Devices

Storage Devices

Storage devices are used to store data that the computer uses. There are 2 types of storage devices, primary and secondary.

Primary Storage

Primary storage devices are used to temporarily store data that the processor needs to perform calculations. Primary storage is stored electronically which means the data can read and written very quickly, but it is volatile – if the computer’s power is turned off, all the data stored is wiped.

Examples of primary storage are:

  • CPU Cache Memory
  • RAM

Secondary storage

Secondary storage devices store data in one of 3 formats – Optical, Magnetic or Solid State. Secondary storage reads and writes data more slowly than primary storage, but the devices are non-volatile – if the power is turned off the data stored still remains.

Examples of secondary storage include:

  • Hard drives
  • Optical Disk Drives
  • SD Cards
  • Pen drives

Storage Devices ( Primary and Secondary) Will be covered in detail in  a future lesson.

Components of a computer system storage devices




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