ORage> (WORM) Any type of stORage medium to which data can be written to only a single time, but can be read from any number of times. Typically this is an optical disk whose surface is permanently etched using a laser in ORder to recORd infORmation. WORM media have a significantly longer shelf life than magnetic media and thus are used when data must be preserved fOR a long time. (1996-04-01)