Storage devices
The primary storage device of a normal PC is a hard drive. Hard drives are mass storage devices which retain data when the computer is switched off. However there are numerous storage devices which will be considered in this course. The main ones are shown below. Also you can see a table with generalised specifications for each device.
Device |
Access Time (ms) |
Transfer rate |
Capacity (Mb) |
Hard drive |
8ms-20ms |
10Mb/s – 90Mb/s |
1Gb – 1 Tb * |
Cd-Rom |
70ms-150ms |
0.5Mb/s – 7.8Mb/s |
800Mb |
Memory Stick |
0.5ms-10ms |
1Mb/s-25Mb/s |
128Mb – 32 Gb * |
Floppy Disc |
~94ms |
~0.05Mb/s |
1.44 Mb |
Magnetic tape |
8s – 62s |
7Kb/s – 120Mb/s |
100Mb – 1Tb * |
* Gb stands for gigabyte which is 1024 mega bytes. Tb stands for Terabyte which stands for 1024 Gb