Storage devices

Computer

1. 1

TIP
Assignment # 1

Names: *Syed Ahmed Khizar
*Syed Abdul Rafay Hassan
Topic: Storage Devices
DISCIPLINE: TS1
SUBJECT: Computer basics

2. 2
Table of Contents
Storage Devices: .................................................................................................................................2
Definition: ......................................................................................................................................2
Example: ........................................................................................................................................2
Classification: .................................................................................................................................3
1-Primary Storage Devices: ..............................................................................................................3
Properties: ..................................................................................................................................3
Example:.....................................................................................................................................3
2-Secondary Storage Devices: ..........................................................................................................3
Properties: ..................................................................................................................................4
Example......................................................................................................................................4
3-Off-line Storage Devices: ..............................................................................................................4
Properties: ..................................................................................................................................4
Example:.....................................................................................................................................4
Functions Of Storage Devices: .............................................................................................................5
Classification On Working Principle: .....................................................................................................5
1-Magnetic Storage Devices: ...........................................................................................................5
2-Optical Storage Devices: ...............................................................................................................5
3-OtherStorage Devices:..................................................................................................................6


Storage Devices:
Definition: A hardware use to store data is called Storage device.
Example:
Correct Wrong
 Hard disk.
 CD (compact Dist)
 RAM
 Folder.
 PDF
 etc

3. 3
Classification: They are classified into three types:
1) Primary Storage Devices
2) Secondary Storage Device
3) Off line storage devices


1-Primary Storage Devices:
Primary storage is a storage location that holds memory for short periods of times while the
computer running.
Primary storage is also called internal memory, main memory, and primary memory.
Properties:
 Fastest memory in computer.
 After reboot it is automatically deleted.
Example:
 RAM
 Cache


2-Secondary Storage Devices:
Secondary storage is a storage medium that holds information until it is deleted or overwritten
regardless if the computer has power.
Secondary storage is also called external memory and auxiliary storage.

4. 4
Properties:
 Any hardware or software problem can affect data.
Example:
 Hard drive

3-Off-line Storage Devices:
Off-line storage that is removable and cannot be accessed by the computer once removed.
Properties:
 Any hardware or software problem does not affect the data.
Example:
 USB (Universal Serial Bus)
 Tape drive
 CD (Compact Disc)
 DVD (digital video disc / digital versatile disc)
 BD (Blu Ray Disc)
 etc

5. 5

Functions Of Storage Devices:
 Read data
 Write data
Classification On Working Principle:
On the basis of working principles secondary and offline storage devices are classified into two
types;
1) Magnetic Storage Devices
2) Optical Storage Devices
1-Magnetic Storage Devices:
 Use magnet to read or write data.
 In 1928, Fritz Pfleumer developed the first magnetic tape recorder, the first magnetic
device.
 Example; hard disk and magnetic tape drive.






2-Optical Storage Devices:
 Use laser and work on principle of geometrical optics.
 Optical tape - more capacity than magnetic tape but not as cost effective.
 Example; CD, DVD and BD.

6. 6

3-OtherStorage Devices:
 Other storage devices work on the principle of electronic.
 Example: USB, Memory card, etc.