The document provides a comprehensive overview of computer hardware and software components, focusing on system architecture like CPUs, memory types (RAM, ROM), and secondary storage devices. It details secondary storage types, including magnetic tapes and disks, along with their characteristics, uses, and limitations. Additionally, it discusses magnetic tape technology as a backup medium, outlining its structure and examples.

1. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Affiliated Institution of G.G.S.IP.U, Delhi
By:
RUCHIKA BAJAJ
ASSISTANT PROFESSOR(IT)
INTRODUCTION TO INFORMATION
TECHNOLOGY
B.COM Into to IT BCOM 107

2. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Computer
Hardware Software
Application
Software
System
Software
CPU Memory I/O Etc.

3. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Fig: Computer

4. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
MOTHERBOARD

5. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
CPU

6. RAM
Memory chips

7. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Affiliated Institution of G.G.S.IP.U, Delhi
RAM & ROM

8. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
SRAM

9. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
DRAM

10. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Ports
CPU
RAM
Disk
controller
Graphics
card
Sound
card
Network
card
Printer
Mouse
Keyboard
Modem Monitor
Speakers
bus
Computer
Fig: Schematic Diagram of a Personal
Computer...

11. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Secondary Storage
• Stores information
• Non-volatile, permanent storage
• Characteristics
– Media
– Capacity
– Access time

12. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Secondary Storage Devices
 Two major types of secondary storage device
1. Serial Devices
– Magnetic tapes (very fast sequential access)
2.Direct Access Storage Devices (DASDs)
– Magnetic Discs
Hard disks (high capacity, low cost, fast)
Floppy disks (low capacity, lower cost, slow)
– Optical Disks
CD-ROM = (Compact disc, read-only memory

13. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Limitation of Secondary Devices

14. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Magnetic Tape
• Sequential access
• Commonly used for backing-up data
• Very large capacity
• Types of magnetic tape
– Tape cartridges
– Magnetic tape reels

15. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Magnetic Tape

16. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Magnetic Tape
• Plastic ribbon 1/2 inch or ¼ inch wide
• 50 to 2400 feet long
• Coated with magnetic material such as iron oxide
or chromium dioxide.
• Data stored in form of tiny magnetized(1) or non
magnetized spots(0)
• Can be erased and reused in definately
• Information can be read many times without
affecting data

17. Magnetic Tape
• What is magnetic tape?
• Thin layer of material capable of storing a magnetic
signal
• Usually contains Iron Oxide
• Protected by backing
layer called the
“Substrate”

18. Examples of Magnetic Media
• Some you are probably familiar with:
• Cassette tapes
• VHS video tape
• Computer Tape
• 8-track
• DAT

19. Magnetic Tape Types
• Tape cartridges
– Backup tape for microcomputer
– Capacities range from 120 MB to 5 GB
– Digital audio tape (DAT)
• Tape reels
– Minicomputer and mainframe
– 1/2 inch wide and 1/2 mile long
– Stores 1600 to 6400 cpi