1.3 Storage Devices

1.3 Storage Devices

1. Characteristics of Storage Devices

   • Capacity how much data can it store
   • Speed how fast can it access the data
   • Portability how easy is it to move it from one place to another
   • Durability how well does it last e.g. if it is dropped
   • Reliability how consistently does it perform
   • Cost how much does it cost per KB, MB or GB?

2. 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

3. Solid State

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

4. 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

5. Secondary Storage