Secondary Storage

Secondary Storage is where software and data are stored when not in use by the processor.

It has no direct link to the processor, instead, data is transferred to Primary Storage (RAM) for processing. For this reason it is considered External Storage because it has no direct role in the processing cycle.

Secondary Storage is non-volatile and is therefore used for long-term storage. This is where you save your work!

Magnetic Hard Disk Drives (HDD)

  • Data stored as magnetised dots on platters
  • Data stored in tracks
  • Allows random access
  • Large(ish) capacity (8TB)
  • Fast transfer speed (128MB/s)
  • Very cheap per Megabyte.

Solid State Drives (SSD)

  • Data stored on integrated circuits (microchips)
  • No moving parts
  • Lower Capacity (due to high manufacturing costs)
  • Transfer speeds vary depending on type


Flash Drives

These are types of Off-Line Storage as they can be removed from the computer and used to transfer data between machines.

  • Data stored on integrated circuits (microchips)
  • No moving parts
  • Slow Read/Write speeds than normal secondary storage.

Examples include Memory Cards and Memory Sticks