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Magnetic Memories: Types, Advantages, and Disadvantages
In this tutorial, we will learn about magnetic memory devices such as magnetic tape memory, magnetic disc memory, floppy disk, and hard disk, and their advantages and disadvantages.
By Saurabh Gupta Last updated : May 11, 2023
1. Magnetic Tape Memory
Magnetic Tapes are a kind of sequential memory that consists of thin plastic ribbons. These plastic ribbons are used to store data and only one of the sides of the plastic ribbon is used for storing data. These plastic ribbons are coated with magnetic oxides. Since it is sequential device's access to data is sequential and hence, read/write speed is slower. This device is highly reliable.
The width of the plastic ribbon generally varies from 4 mm to 1 inch and it has a storage capacity of 100 MB to 200 GB.
Advantages
The following are the advantages of magnetic tape memory:
- These are low-cost memories (cheap in comparison to RAMs).
- These memories can be reused.
- It can be used for storing large files.
- It is used for copying from disk files.
- These are generally compact in size and are easy to store.
Disadvantages
The following are the disadvantages of magnetic tape memory:
- Since sequential access is made to data, we can't access data at random from in between.
- It is vulnerable to humidity and dust; hence it requires special caring for storage and a suitable environment is needed to store these magnetic tapes.
- Data stored in these devices are hard to update.
2. Magnetic Disk Memory
A magnetic disk is a type of secondary storage device that uses a magnetization process to read, write, and access data. The Magnetic disk is made up of a set of circular platters. It is covered with a magnetic coating to store information and stores data in the form of tracks, spots, and sectors. These are less expensive than RAM, but since it is a kind of secondary storage device access to information is slower. Updating data in the magnetic disk is easier and it also allows random access to information in between. Floppy disks and hard disks and are common examples of magnetic disks.
Advantages
The following are the advantages of magnetic disk memory:
- These are cheap in price.
- Since, it is not sequential, random and straight access to data is possible.
- It has better data transfer rates as compared to magnetic tapes.
- These are less prone to data corruption as compared to magnetic tapes.
Disadvantages
The following are the disadvantages of magnetic disk memory:
- Magnetic disks are costlier than magnetic memory tapes.
- Sequential access is prohibited.
- It is vulnerable to humidity and dust.
Types of Magnetic Disk Memory
The following are the types of magnetic disk memory:
2.1. Floppy Disk
Floppy disk is a smaller, simpler, and cheaper magnetic disk that is made by a flexible Mylar plastic diskette coated with a thin film of magnetic material. It is generally enclosed in a square plastic body which supports its handling. A small hole named as index hole is used for referencing all the tracks. Earlier, it was used as the main storage device, but as time passed, it was later used for carrying data from one computer to another. Nowadays, floppy disks are not used. These are prone to viruses and also data in these devices may get corrupted easily.
2.2. Hard Disk
Hard Disks are a kind of magnetic disk made of aluminum. It consists of thin plates (known as a platter) which are coated on both sides with magnetic oxide. It is used as the main storage device on the computer. Both sides of the disk are used for storing data except the upper side of the uppermost disk and the lower side of the lowermost disk. These are costly as compared to floppy disks. It is a reliable form of memory and data stored in a hard disk cannot be damaged or corrupted.