Secondary Storage

Secondary Storage

1. Optical

   • Definition
     • Optical storage is the storage of data on an optically readable medium (a shiny disc that reflects light) .
   • Characteristics
     • Capacity
       • DVD: 4.7GB
       • CD:720MB
       • Blu-Ray: 25GB
     • Speed
       • 50Mbps
     • Portability
       • Very good
     • Durability
       • Degrades Over Time
     • Cost
       • 25GB: 44p
   • Examples
     • DVD
     • CD
     • Blu-Ray

2. Magnetic

   • Definition
     • Magnetic storage is the manipulation of magnetic fields on a medium in order to record audio, video or other data.
   • Characteristics
     • Capacity
       • 10TB max.
     • Speed
       • Slow
     • Cost
       • Cheap
     • Portability
       • Not the best
     • Durability
       • Very
   • Examples
     • Hard disk drive
     • Floppy disk
     • VHS

3. Solid State

   • Definition
     • Solid-state storage devices are based on electronic circuits with no moving parts
   • Examples
     • USBs
     • SD cards
     • Smart cards
   • Characteristics
     • Speed
       • Not too fast
     • Portability
       • Extremely
     • Cost
       • 16GB: A couple pounds
     • Durability
       • Very
     • Capacity
       • 4TB max.