Orange is a reference to the fact that red and yellow mix to orange. This correlates with the fact that CD-R and CD-RW are capable of audio ("Red") and data ("Yellow"); although other colors (other CD standards) that do not mix are capable of being burned onto the physical medium. Orange Book also introduced the standard for multisession writing.
ISO 9660, a 1986 filesystem standard used in conjunction with CD-ROM formats.
Orange-Book-Standard, a decision named after the Compact Disc standard, issued in 2009 by the German Federal Court of Justice on the interaction between patent law and standards