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A standard CD-ROM format developed by Philips for CD-i. It is ISO 9660 compliant and uses mode 2 form 2 addressing. It can only be played on drives which are XA (Extended Architecture) compatible.
Many Green Book discs contain CD-i applications which can only be played on a CD-i player but many others contain films or music videos. Video CDs in Green Book format are normally labelled "Digital Video on CD"
Green Book was obsoleted by White book CD-ROM in March 1994.