Answer:
The types of secondary memory on the basis of data acess are:
- Magnetic tape: magnetic tape is one of the most popular sequentially accessible storage mediums for large data. It is device used for storing back up information. It is made up of Mylar plastic coated with iron oxide on only one side of tape Data is stored in frames across the width of the tape. It is a serial access type storage ever having low cost and has large storage capacity. When a large volume of information is to be processed sequentially it can be stored on magnetic tape, They are durable, can be written, erased, and re written.
- Magnetic disk: Magnetic storage devices refer to system that keeps information or data is magnetized material. In this technology data is stored and read with the help of magnetic properties developed while applying electricity on a magnetized medium Magnetic storage offers high storage capacity, reliability and be capacity to directly accessing data. Magnetic disk holds more data in small place and attains faster data access speed. Data can be accessed randomly from magnetic disk.
- Hard disk: Hard disk is the most common secondary storage device for all computers. It is the storage medium within the computer that stores large amount of data and provides relative quick access to that data. A hard disk uses and flat aluminum disk called platters. These platters are coated with a special iron oxide or ferric mode material on both sides to store data in the form of magnetic patterns. Platters are mounted by cutting a hole in the centre and stacking them onto a spindle.
- Zip disk:They are high capacity removable disk and drive. They have the speed and capacity of hard disk and portability of floppy disk. Zip disk are of the same size as floppy disk, that is:3-½ inch but have a much higher capacity than the floppy disk, Zip disk and drive were made by Iomega Corp. It comes as a complete unit disk, drive, connection cable, power cord and operating system. It can be connected to the computer system externally using a parallel chord or SCSI cable. Their capacity ranges from 100 MB to 750 MB. They can be used to store large files, audio and video data
- Flash memory: Flash memory is a long-life and non-volatile storage chip that is widely used in embedded systems. It can keep stored data and information even when the power is off. It can be electrically erased and reprogrammed.
