Scanner (nowadays this is in mobile itself, not very much used)
CPU – This is the processing unit
Main Memory: RAM: This determines how fast the computer works
Expansion cards
Power supply unit
CD Drive – External storage device
Hard disk: This determines how much storage capacity
Motherboard: This is where all instructions are wired together and helps the computer work
Speakers
Monitor
Operating System
Application Software
Keyboard
Mouse
External Hard Disk
Printer
Projector

Source: Wikimedia commons

Safely operating a computer

Explore a computer