A disk (or diskette) is a flat, round plate on which data can be encoded and stored. Fixed disks in the form of hard disks are a common component of a computer’s storage system, but most other forms of disk hardware ( floppy disks, CD-ROMs, etc.) have become obsolete.

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.