disk v. disc

In general usage, the word for a flat, round object can be either ‘disk’ or ‘disc’. Americans favor ‘disk’ and the British usually stick with ‘disc’.

In the context of digital media, these words have distinct meanings. Disks are rewritable magnetic media within a case, like hard disks and floppy disks. If the disk’s casing also contains the mechanisms that read from and write to the disk, the entire enclosure is called a drive. Internal hard drives are intended for long-term installation inside a computer.

Discs are usually unencased optical media, such as CDs and DVDs. Some discs are read-only, others can be written to once, and others can go through many erase and rewrite cycles. Discs are removable media that can be ejected from a computer.

Apple on disk v. disc

wiseGEEK on disk v. disc