IBM 3363 Optical WORM

File Format
Name	IBM 3363 Optical WORM
Ontology	Physical File Formats Optical Discs IBM 3363 Optical WORM
Released	1987 (?)

IBM 3363 Optical WORM discs were a predecessor to CD-Rs.

200MB capacity, 512 byte sectors, custom filesystem.

Sectors could be written once but thereafter could not be modified. However, sectors could be deleted after writing, but deleted sectors could not be undeleted or reused.

• IBM Technical Reference Manual (1987)