This document discusses different types of secondary storage devices including magnetic tape, magnetic disks, and optical disks. It describes the key characteristics and components of each type of storage device. Specifically, it covers how magnetic tape provides sequential access and large storage capacities. It also explains how magnetic disks can provide both direct and sequential access and compares floppy disks and hard disks. Finally, it outlines common optical disk formats like CDs, DVDs, and their read-only, write-once, and rewritable variants.

1. Information Technology for Managers Session 3 By Prof. Arun Mishra

2. Learning Objectives In this chapter your will learn about: Classification of Secondary Storage. Magnetic Tape Magnetic Disk Optical Disk Memory Storage Devices.

3. Limitations of Primary Storage

4. Secondary Storage Stores information Non-volatile, permanent storage Characteristics Media Capacity Access time

5. Classification of Secondary Storage

6. Sequential-access Devices

7. Direct/Random-access Devices

8. Magnetic Tape Sequential access & Very large capacity Storage capacity is measured in bytes per inch ( bpi). Data transfer rate is measured in bytes per second (bps) . Commonly used for backing-up data Medium is plastic ribbon usually ½-inch or ¼-inch wide & 50 to 2400 feet long. Surface is coated with recording material that can be magnetized. Data is recorded on the coated surface as tiny, invisible magnetized & non-magnetized spots.

9. Storage Organization

10. Storage Organization

11. Types of Magnetic Tapes Tape cartridges

12. Types of Magnetic Tapes 2. Magnetic tape reels

13. Magnetic Disks

14. Storage Organization

15. Types of Magnetic Disks Floppy Disks Portable and removable Flat circular Mylar media Magnetic charge on metal oxide film coating Standard 2HD 1.44 MB Parts Tracks Sectors

16. Types of Magnetic Disks Hard Disks Metallic disks Fast retrieval, greater capacity Read/write heads ride cushion of air .000001” thick Three types Zip/Bernoulli disk Hard-disk pack Winchester disk

17. Optical Disks

18. Storage Organization

19. Access Mechanism

20. Access Mechanism

21. Types of Optical Disks CD-ROM (Compact Disk Read Only Memory) CD-R (Compact Disk Recordable) CD-RW (Compact Disk Read/Write) DVD (Digital Video/Versatile Disk) DVD-ROM DVD-R DVD-RAM or DVD-RW

22. Memory Storage Devices There are three types of memory storage devices: Flash Drive (Pen Drive) Memory Card (SD/MMC) RAM Disk

23. Flash Drive (Pen Drive)

24. Flash Drive (Pen Drive)

25. Memory Card (SD/MMC)

26. RAM Disk