Magnetic Disks: Advantages, Disadvantages and Uses

 

Advantages of Magnetic Disks:

 

Magnetic disks support direct access of data making them more suitable for a wide range of applications.

 

Due to random access property, magnetic disks are often used by multiple users simultaneously as a shared device.

 

Magnetic disks are suitable for both online and offline storage of data.

 

Except for fixed type Winchester disk, storage capacity of other magnetic disk is virtually unlimited because as many disks as required can be used for storing very large data sets.

 

Due to their low cost and high data recording density, cost for a bit of storage is low for a magnetic disks. An additional cost benefit is that magnetic disk can be erased and reused many times.

 

Floppy disks and zip disk being compact in size and light in weight are easy to handle and store. They enable storage of very large amount of data in a small storage space.

 

Floppy disks and zip disks are also easily portable from one place to another. They are often used to transfer data and programs from one computer to another that are not linked together.

 

Any information desired from disk storage can be accessed in a few milliseconds because it is a direct access storage device. This is not possible with tape storage, it being a sequential access storage device.

 

Data transfer rate for a magnetic disk system is normally higher than a tape system.

 

Magnetic disks are less vulnerable to data corruption due to careless handling, unfavourable temperature and humidity conditions than magnetic tapes.

 

 

Disadvantages of Magnetic Disks:

 

Although magnetic disks can be used for both type of applications (random as well as a sequential data processing applications), use of magnetic disk is less efficient than magnetic tapes for sequential applications.

 

It is more difficult to maintain security of information stored on those magnetic disks that are used as shared, online secondary storage devices as compared to information stored on magnetic tapes or on other types of magnetic disks.

 

For Winchester disks, a disk crash or drive failure often results in loss of entire data stored on it. It is not easy to recover the lost data. Hence, suitable backup procedures are suggested for data stored on Winchester disk.

 

Some types of magnetic disks such disk packs and Winchester disk, are not as easily portable as magnetic tapes.

On cost per bit basis, cost of magnetic disk is low but the cost of magnetic tapes is even lower.

 

They must be stored in a dust free environment.

 

Floppy disk, zip disk and disk packs should be labelled properly to prevent erasure of useful data by mistake.

 

 

Uses of Magnetic Disks:

 

Magnetic disks are used for following purposes:

 

For applications that require random data processing.

 

As a shared, online secondary storage device. Winchester disks and hard disk packs are often used for this purpose.

 

As a backup device for offline data storage.

 

Archiving of data that are not used frequently but may be used occasionally. Floppy disk, zip disk and disk packs are often used for this purpose.

 

Transferring of data and programs between two computers that are not linked together. Floppy disks and zip disks are often used for this purpose.

 

Distribution of software by vendors. originally sold software or software updates are often distributed by vendors on floppy disks and zip disks.