1. Backing Storage

2. Magnetic Storage Hard and floppy Disks tracks Sector Block – track 3 sector 1

3. Magnetic Storage - Disks Disk surfaces coated with iron coating Particles can be magnetised to point North(1) or South(0) When a file is saved the operating system makes a note of the filename and which track/sector block it is saved to File can be found again by direct (random) access – going straight to the block

4. Magnetic Tape Used for Backup Sequential (Serial) Access – Must read through all earlier files to find one File 1File 2File 3File 4 File 5File 6

5. Optical Storage Land Pit Las er Sen sor Las er Sen sor Las er Sen sor Aluminium Layer 1 10