Floppy disks are commonly used as secondary and backup storage media in micro computers. They are popularly called diskettes. These diskettes are very thin and flexible and hence, they are called floppy. The floppy disks are made of a thin film of plastic coated with a metallic oxide. It is kept in a square protective cover made of thin plastic, called jacket. The disk rotates freely in that jacket. The 5.25 inch disk has an index hole that is used as a reference to count the sectors. It is used to locate the first sector of the track. A plastic hub ring is fitted at the center of the 5.25 inch floppy disk to protect the internal edge of disk from drive spindle.
They are small, convenient and inexpensive. They are removable disk. A floppy disk can be inserted into the disk drive when needed.
How does a floppy disk work?
The surface of the floppy disk is divided into a number of concentric circles called tracks. Data are recorded on the tracks in the form of magnetic spots (representing 1 or 0; spot representing 1 is magnetized in one direction and the spot representing 0 in the other direction) Each track is divided into a number of sectors.
Tracks and sectors are not physical areas but they are logical areas. There is a large hole at the center of the disk for the spindle of the disk drive. There is a window to facilitate read and write operation. The device which performs the reading and writing on the disk is called read/write head.
Reading and writing
The floppy disks are inserted in a floppy disk drive unit to perform reading and writing operations. The head is placed inside the floppy disk drive.
The read and write window of the disk allows the head to touch the disk surface for read-write operation. While writing on disk, the read-write head converts the computer's electrical impulses into magnetic field. While reading form floppy, the read-write head converts the magnetic field into electrical impulses. During reading and writing, the disk rotates to the appropriate position and the head physically makes contact with the disk. The access time of floppy disk is 100 milliseconds to 600 milliseconds.
On the 5.25 inch floppy disk read-write window is a hole cut into the cover or jacket but on the 3.5 inch floppy disk, the read-write window is covered by a sliding metal cover known as a metal slide. The disk drive pushes this cover aside when the disk is inserted in to the drive.
There is a write protect notch to protect the stored information. AN adhesive tape ( black or silver ) is supplied with each floppy when you purchase it. It is called write-protect tab. If a tab is fixed on the notch, then the computer will not be able to write on that disk. It can't also erase the information stored on the disk. This protects of the disk from accidental erasing of information. If you want to write something on the disk, you have to remove the tab. These tabs are used only in 5.25 inch disks. In 3.5 inch disks the write protecting of data is done with the help of a plastic button. The plastic button can be slides into either of two positions. One position permits reading ,writing and erasing. The other position permit only reading the button slides in a track. When light is visible through the track, then the disk is write protected.
They are small, convenient and inexpensive. They are removable disk. A floppy disk can be inserted into the disk drive when needed.
How does a floppy disk work?
The surface of the floppy disk is divided into a number of concentric circles called tracks. Data are recorded on the tracks in the form of magnetic spots (representing 1 or 0; spot representing 1 is magnetized in one direction and the spot representing 0 in the other direction) Each track is divided into a number of sectors.
Tracks and sectors are not physical areas but they are logical areas. There is a large hole at the center of the disk for the spindle of the disk drive. There is a window to facilitate read and write operation. The device which performs the reading and writing on the disk is called read/write head.
Reading and writing
The floppy disks are inserted in a floppy disk drive unit to perform reading and writing operations. The head is placed inside the floppy disk drive.
The read and write window of the disk allows the head to touch the disk surface for read-write operation. While writing on disk, the read-write head converts the computer's electrical impulses into magnetic field. While reading form floppy, the read-write head converts the magnetic field into electrical impulses. During reading and writing, the disk rotates to the appropriate position and the head physically makes contact with the disk. The access time of floppy disk is 100 milliseconds to 600 milliseconds.
On the 5.25 inch floppy disk read-write window is a hole cut into the cover or jacket but on the 3.5 inch floppy disk, the read-write window is covered by a sliding metal cover known as a metal slide. The disk drive pushes this cover aside when the disk is inserted in to the drive.
There is a write protect notch to protect the stored information. AN adhesive tape ( black or silver ) is supplied with each floppy when you purchase it. It is called write-protect tab. If a tab is fixed on the notch, then the computer will not be able to write on that disk. It can't also erase the information stored on the disk. This protects of the disk from accidental erasing of information. If you want to write something on the disk, you have to remove the tab. These tabs are used only in 5.25 inch disks. In 3.5 inch disks the write protecting of data is done with the help of a plastic button. The plastic button can be slides into either of two positions. One position permits reading ,writing and erasing. The other position permit only reading the button slides in a track. When light is visible through the track, then the disk is write protected.
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