Hardware Description

Storage System

External storage devices:

The storage capacity of Personnel Computers is limited, it presents a limitation on the volume of data to be stored.

However , this is not only drawback. Once the Personnel Computer is switched off or in case of power failure, all data stored in internal storage (RAM) is lost.

This means every time, you want to work, you would have to input data required for processing.

To permanent store data, external storage media can be used with Personnel Computer also called as secondary storage device.

There are 3 type of devices used with modern Personnel Computer.

A. Floppy Disk

B. Hard Disk

C. Compact Disk

CPU does not perform task of writing and reading the data it is done by a electro -

mechanical device, where Floppy disk or Compact disk to be insert called Floppy Disk Drive or CD-Rom Drive respectively.

In case of hard disk it named as Hard disk drive. Since these devices perform writing as well as reading, so they called input-output devices.

Basic differences between these devices.

Flopy Disk Compact Disk Hard Disk Floppy Disk is Suitable for moving data from one computer to another. Compact Disk is also Suitable for moving data from one computer to another. Hard Disk is not Suitable for moving data from one computer to another. Not Reliable Can be damaged by heat, dust and accidental twist. Reliable against dust heat etc. Prone to damage, since it is within Personnel Computer. Floppy disk: can store 1.44 MB data. Compact Disk: Capacity of 660 MB. Hard Disk: Capacity of 80GB or above. Floppy disk: Contain Write Protection notch to prevent writing. Compact disk: Required CD writer to record the information on it. Hard Disk: Perform Read/Write operation.