Memory.

Memory.

1. Optical

   • A laser light creates marks in a pattern on the disk
   • A laser light detects where the marks are and translates this into a readable format

2. Solid state

   • This is made of microchips (switches)
   • The state of the switches determine if a 1, or 0 is stored

3. Magnetic

   • Read/write move across the medium and change how magnetised that part of the medium is
   • E.g. one level of magnetism will be a 1, a second will be a 0

4. Secondary storage

   • Long term storage of data, files, software, OS.
   • Why do we need to store these things?
     • To access it again later To use software To interact with the computer
   • What would happen without secondary storage?
     • Software would need to be installed each time we use it You couldn’t save any files, data, images, videos etc.