Floppy disks, or diskettes, are made from a flexible plastic that is coated with a magnetic oxide. The floppy disk drive encodes this oxide with the data generated by the computer. After you turn your system off, unlike electronic RAM, the encoded oxide retains this data. Your data can then be read by the floppy disk drive at a later time.
The magnetic oxide coating on the floppy disk will hold its encoded data almost indefinitely unless you deliberately erase it. This is done intentionally when you want to update the information stored on the diskette.
The plastic disk is safely protected by a thin cardboard jacket. The diskette spins inside this jacket, allowing the entire surface of the diskette to be scanned by the drive’s circuitry. Data is read from or written onto the diskette through the
Normally, the computer will write new information onto the unused space on the diskette. If there is no unused space, your computer will inform you that the disk is full. You can instruct the computer to write over the information that is already on the diskette. You might do this to update an inventory file, or change an address and phone number in a database.
Caution!
Updating, or overwriting, data stored on a diskette will erase the old information. Under most circumstances you cannot get it back.