Red Book is the name of the CD-DA (CD-Digital Audio) standard as originally defined by Sony and Philips. It defines the format that a CD must have in order to be played on an audio CD player, and describes what a CD player must do in order to properly play audio CDs. Any CD which is "Red Book Compatible" should be able to be played on any audio CD player.Orange Book is the name of the CD-WO (CD-Write Once) standard. It defines the format of a write-once CD, not only for audio, but also for data (CD-ROM). The orange book specification is designed such that Red Book compatible CDs can be created on a write-once disc. The orange book, in effect, defines a super-set of the Red Book specifications.