Some drives are called discs and other drives are called disks.
Optical discs like CDs are spelled with a "c," and other kinds of computer storage media such as floppy disk drives and external hard drives are spelled with a "k."
Although there is some disagreement, Stedman's medical dictionary recommends the spelling "disc" for all medical uses. You can remember that "optical" has a "c" in it and the spelling "disc" for optical drives and biology (like your optic nerve) also are spelled with a "c."
I stored my data on a compact disc.
I have a slipped disc in my back.
Does anyone use floppy disks anymore?
The disk failed in my external hard drive.
Get more tips like this in The Grammar Devotional: