Hardware & Software

Hardware Components

Hardware refers to the physical components of a computer system.

Categories

  • Input Devices - Keyboard, mouse, scanner, microphone, webcam
  • Output Devices - Monitor, printer, speakers, projector
  • Processing - CPU (Central Processing Unit)
  • Storage - HDD, SSD, USB drives, optical discs

Storage Units

Unit Size
1 Byte8 bits
1 Kilobyte (KB)1,024 bytes
1 Megabyte (MB)1,024 KB
1 Gigabyte (GB)1,024 MB
1 Terabyte (TB)1,024 GB

Software Types

  • Operating Systems - Windows, macOS, Linux - manage hardware and provide user interface
  • Utility Software - Antivirus, disk cleanup, file compression
  • Application Software - Word processors, spreadsheets, databases, web browsers

Boot Process

  1. Power on - electrical current flows to components
  2. POST (Power-On Self-Test) - checks hardware is working
  3. BIOS/UEFI loads - basic input/output system initialises
  4. Boot loader - finds and loads the operating system
  5. OS loads - operating system starts and presents user interface