What is a Disk? Alternatively known as a diskette, a disk is a hard or floppy round, flat, and magnetic platter capable of having information read from and written to it. The most commonly found disks with a computer are the hard disks and floppy disks ( floppy diskette) shown in the picture.

There are two basic types of disks in the computer hardware realm: magnetic disks and optical disks. Data is encoded to magnetic disks using magnetized polarities; this means flux reversals between positive and negative domains on the disk are interpreted as binary data.