An abbreviation for Compact Disc-Recordable -- a Compact Disc on which a user can record audio, data, or both. (The acronym CDR is also in common usage.) A CD recording drive ("CD Burner") uses a higher-power laser (as compared to a standard CD drive) to record information in a special dye layer in the blank media. Once information is recorded to the disc, though, it cannot be removed. (It can be 'deleted' but this only removes the directory entry, not the data storage itself.)

CD-Rs have the benefit that they can be played in almost all CDROM drives and audio CD players (assuming that the CD contains audio). A similar technology, CD-RW, is erasable but cannot be read by many CD players and earlier CDROM drives.