Secondary Storage Media

Secondary Storage Media Points : Describe secondary storage media Magnetic Tape Storage Its looks like the music cassettes tape with magnetic coating the amount of data is measured in term of cpu and dpi. Tape contains tracks or channels tape unit is used to read & write on tape. In the tape disk the data is stored in the shape of records. Magnetic Disk Storage Another type of secondary memory a hard disk is a metal platter coated with magnetic Oxide come in a variety of 8”, 5¼”,31,2” inches diameter. Several disk are assembled together in a disk pack. Every data has a top & bottom surface on which data is recorded. Surface has magnetic spots on the tacks. number of tracks vary from disk to disk. Magnetic disk is a direct access storage device. It access record randomly. A floppy disk drive rotates disk 300 to 400 revolution per minute and hard disk 3600; evolutions per minute. Sectors Each track on a disk is divided into sectors that a specific number. Cylinder To minimize the seek time data may be stored by cylinder method. Caching Caching is a technique that uses restively small amount of semi conductor memory called a cache to speed up the performance of a disk
1024 Bytes = 1 KB (Kilo byte)