optical disk

n.A platter used to store large quantities of data that can be read using light.

Notes

Data may be stored as an analog or digital signal. Most optical systems use a laser to read the data. Optical disks that are mass produced, such as commercial LaserDiscs and compact discs, may be recorded mechanically by stamping. Some optical disk formats record data using laser light, including write-once read-many (WORM) and writable compact disc formats.