A floppy disk looks like a 45 rpm record encased in a square jacket. They have been named so because they are flexible. They can hold data from new tenths of a megabyte. This depends upon factors such their size and nature of magnetic material. They are available in 8 inches, .25 inches and 3.5 inches. They are also classified to be single or double –sided and may have normal, double or high density. In the high definition category that diskettes with capacity 2.88 mega byte are also available.
They are mostly used for input on microcomputers. As regards its construction a floppy disk consists of a light flexible disk enclosed in a cash board or plastic jacket. A disk drive is used to read and write the data. A part of the magnetic surface is exposed to allow contact with the read write heads. The disk controller looks for the index hole that marks the location of the first track. When index hole is detected the controller begins reading data from the specified track in smaller disks. The area is protected by a sprung metal cover. The floppy disks were originally developed in 1971 as a replacement for cards and they have highly successful in this role.
A disk which when you pick it up you feel it go all loose and floppy and then the end starts to bend and all of it then bends and by the it it gets so floppy you have to drop it !
It is the disc that you can use to put/retreive data on a computer. They have now been replaced by DVDs or Cds.
Floppy disk is made up of flexible plastic which is coated with ferromagnetic compound. The disk is housed in a protective jacket having several holes cut in it which perform as given below.
Write protect notch: if write protect notch is opened, data can not be entered on the disk and no alternation can be done in the previous data. If the slot is sealed then data can be entered on the disk and alternations can also be done in it.Central hole: floppy get fixed on a rotating rod or the spindle and can revolve. Index hole: next the central hole is located a small hole used to identify the starting position of the track.
Read and write hole: disk drive head R/W using this hole can read and write the data. The data is stored on about 2 cm strip of the disk. Floppy disk can store a data of about 1.44 MB. The hard disk is installed inside the system unit. It is made of aluminium hence it is not flexible. It is enamelled with a layer of a material that can be magnetized easily. Hard disk has higher speed and larger capacity as compared to other disks. This disk is also called the storage disk.