Secondary Storage

Secondary Storage

1. Secondary storage is non - volatile and is the permanent storage of data. It is needed in a computer system to store files and programs .

   • Non- volatile : Is where the data is not deleted when the computer is turned off.

2. Optical Storage:

   • Examples
     • DVDs or Blu-ray discs
     • CD - ROMs
   • It is not very Durable - Unlike Solid State - and has very limited capacity meaning you can't fit much onto it .
   • An Advantage of optical storage is that it is cost effective and very portable -compared to solid state- meaning you can take it somewhere easily.
   • Data is burned onto the surface of the disk using a laser and a laser beam is also used to read the data from the optical device.

3. Solid State (Flash) Storage

   • It is less cost effective in comparison to magnetic as it has much smaller capacity therefore it can't fit as much data onto it.
     • Also has a limited read , write speed lifespan.
   • Uses microchips to store data instead of magnetised disks ( magnetic storage ) and doesn't contain moving parts- therefor is more durable.
   • Examples
     • USB sticks
     • Flash memory devices
   • It is more durable compared to Optical and Magnetic storage and Can read + write data much faster compared to magnetic storage.
     • Also it is more energy efficient

4. Magnetic Storage:

   • Not as durable as has moving parts and a slower read / write speed compared to solid state.
   • It is more cost effective as it has a larger capacity compared to solid state.
   • Examples
     • Floppy disks
     • Hard drives / disks.
   • Contains moving parts - unlike solid state- and therefore isn't as durable. A magnetic drive contains a number of platters which move at a high speed.