Advantages

Magnetic disks support direct access of data making them more suitable for a wide range of applications compared to magnetic tapes which support only sequential access of data. Due to random  access property computer often use magnetic disks as a share device,  which is shared simultaneously by multiply user, for example computer often use Winchester disks packs as on-line secondary storage devices storing data of multiply users of a computer system  A  taps is not suitable for such type of usage due to its sequential-access property.

Magnetic disks are suitable for both on-line and off-line storage data. For example Winchester

Disks and disks packs are often use as on-line secondary storage devices whereas.  Floppy disks and zip

disks are  used as off-line secondary  storage device In fact, high capacity Winchester disks have possible for  today’ s most personal computer user to enjoy the convenience of having all data and software readily accessible at all times. Except for fixed type Winchester disks, storage capacity of other magnetic   disks 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 densities, cost per bit of storage is low for magnetic disks an additional cost benefit comes from the fact that we can erase data on a magnetic disks and reuse it many times. Due to their compact size and high data recording densities, they enable storage of very large amount of data in a small storage space.

Zip disks are easily portable, and user often is use them too transfer data and program between two unlinked computers. Data access rate for a magnetic disks system is normally much superior a tape system. Magnetic disks are less vulnerable to data corruption due to careless handling or unfavorable temperature and humidity condition than magnetic tapes.

Limitations

Although magnetic disks are usable for both random and sequential data processing application, their usage for sequential applications is less efficient that magnetic tapes.

It is more difficult to maintain security of information stored on magnetic disks used as shared, on-line 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 result in loss of entire data stored on it. It is not easy to recover the lost data. Hence, data stored on Winchester disks requires suitable backup procedures.

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

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

Magnetic disks must be stored in a dust-free environment.

We must label zip disks and disk packs property and logically to remember what data is on which disk/disk pack, and to prevent erasure of useful data by mistake.

Source: Computer Fundamentals Sixth Edition >> Pradeep K. Sinha Priti Sinha