disc - technical definition

An alternate spelling for disk with a "k." Some computer manufacturers use this spelling for magnetic disks, but "disc" usually refers to optical media, such as CDs and DVDs.

In this Encyclopedia...
Disc ("c") refers to pure optical media, and disk ("k") refers to magnetic hard and floppy disks as well as to disks that use a combination of magnetic and optical (see magneto-optic disk).