Magnetic had disk drive

Computers have a (secondary) storage device called a disk drive, It is where all your apps are stored. There are currently two types of storage device, the magnetic hard disk drive and the solid state disk drive.

A computer (unopened)
A computer (opened) - Magnetic hard disk shown
A working magnetic hard disk drive

​Magnetic had disk drive labelled

How does it work when I click save?

  1. The spindle spins the platter.
  2. The actuator arm moves across the platter.
  3. Your saved information moves down the actuator arm to the read/write head.
  4. The head changes the polarity in a particular sector (an area on the platter - see below) on the platter to either a number of north poles or south poles.
  5. Having e.g. North pole, South pole, North, North, South etc is much like ones and zeros of binary (as per diagram on left).