It Presentation

TOPIC : STORAGE AND COMMUNICATION HARDWARE SUBMITTED TO: SIR IBRAHIM SUBMITTED BY: SAAD AKMAL Student Of B.B.A 1 REG # 2411308006 DATE: 14TH JAN 09

INTRODUCTION Hours worth of work can be saved, transmitted across the country, or lost in the blink of an eye when using a computer system. One of the most common mistakes new computer users make is forgetting to copy important data and programs to another tape or disk.

STORAGE MEDIA  The term storage media refers to the material on which data is recorded; tapes and disks are the most common.  Disks are the most commonly used storage media because they support direct access to data.  Magnetic disks are popular because they can be erased and reused.

STORAGE MEDIA

MAGNETIC DISK STORAGE  Disk drives are equipped with read/write heads that convert the magnetized spots on disk into a binary code.  As the disk spins inside the drive, the read/write head passes over the surface of the disk. The head writes data on the disk by magnetizing spots on the disk’s tracks and retrieves data from the disk by reading magnetized spots already there. 1 byte = 8 bits  Moisture and extreme heat or cold are bad for any disk.

MAGNETIC DISK

HARD AND FLOPPY DISKS  The primary types of disk drive use either hard disks or floppy disks.  when compared with floppy disk drives, hard disks provide users with fast access to stored data.  Hard disks come in a variety of sizes, from about a 14-inch diameter for mini computers and mainframes , 1.3-inch diameter for portable personal computer systems.

HARD AND FLOPPY DISK

DISK STORAGE

 Disks drives store data on disks in concentric circles called disk tracks which are subdivided in storage locations called sectors

DISK STORAGE

 A collection of hard disk platters stacked on the top of each other creates a high capacity storage unit called a disk pack

 A collection of tracks that can be read at one position of the access mechanism is called a cylinder

DISK PACK

REMOVABLE AND FIXED DISKS  Disk packs can inserted into a disk drive for temporary use or installed permanently within the drive Such disks are called removable or fixed disks .  Removable disks are versatile in use because they can be inserted and removed  Fixed disks are built inside the computer case and sealed from the outside environment to protect the disk .An access light on the front panel is turned on when data is being read or written

REMOVABLE DISK

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