Storage

Storage

1. Primary and Secondary Storage

   • Primary
     • In chips inside the computer
     • Two Types
       • RAM
         • Fast, Temporary Storage
         • Volatile Memory
           • Contents disappears when there isn't power
         • Read/ Write can be altered by User
         • Random Access Memory
       • ROM
         • Permanent Memory
         • Held on Computer Chip
         • Non- Volatile
         • Contents cannot be altered by user
         • Read Only Memory
     • Available immediately by the CPU
   • Secondary
     • Outside the computer/ within the casing
     • Short delay when obtaining data
     • Examples
       • Magnetic Disc
       • Magnetic Tape
       • CD-ROM
       • CD-RW
       • DVD
     • Backup Storage

2. Memory Size

   • The more memory the:
     • Applications run faster on their own
     • More applications able to run at the same time
     • Can move quicker between applications

3. Measuring Storage Capacity and Performance

   • Storage Capacity
     • How much data can the storage device/media hold?
   • Storage Density
     • How compact is the storage device?
     • As much storage as possible in the smallest size
   • Access Time
     • Time it takes to access a particular piece of Data
     • Corresponding time for the storing of the data
   • Transfer Rate
     • Once the data is located it will need to be read and transferred
     • Measures the throughput of the data
   • Portability
     • The ease in which the storage device can be removed
   • Physical Size
     • Small and Light as possible