Glossary for Geospatial Science

WORM drive:  (historical term)  Write Once, Read Many drive.  A type of drive that reads and writes to non-erasable optical disks, which are used for permanent, file storage.  WORM disks are empty when purchased, and the user can write files to them until they are full.  Data is recorded with reflective pits in the coating laid on the surface of a glass or metal disk.  Once the pits have been burned into the coating, they cannot be removed, which makes this medium non-erasable.  (See also: erasable optical cartridge, erasable optical drive, optical disk)