1.3 Storage

1.3 Storage

1. Solid State

   • made of microchips (switches)
   • the state of the switches determine if a 1 or 0 is stored
   • e.g. Solid State drive, SD Card, USB Memory Stick
   • flexible/ inexpensive/ portable/ robust/ faster access to data

2. Magnetic

   • read/write move across the medium
   • change how magnetised that part of the medium is
   • e.g. one level of magnetism will be a 1 and the second will be 0
   • e.g. Hard disk drive, Tape drives
   • can store a large capacity/ commonly used making it possible to share compatibility

3. Optical

   • laser light
     • creates marks in a pattern on disk
     • detects where marks are and translates them into a readable format
   • e.g. Blu ray, DVD ROM, CD ROM
   • inexpensive/ reliable/ robust/ relatively large capacity

4. characteristics

   • a feature, attribute or distinguishing trait
   • characteristics of a storage device
     • capacity (how much data can it store?)
     • speed (how fast can it access data?)
     • portability (how easy is it to move it from one place to another?)
     • durability (how well does it last?)
     • reliability (how well does it perform?)
     • cost (how much does it cost per KB/MB etc?)

5. UNITS OF STORAGE (Highest to lowest)

   • GB (1000000000 bytes)
     • MB (1000000 bytes)
       • KB (1000 bytes)
         • Nibble (4 bytes)
           • byte
             • bite

6. Secondary Storage

   • Where devices are not constantly connected to the computer
   • Used to back up data
   • Need for larger storage capacity