Black Book is an unofficial designation of optical disc (OD) formats that defy official standards for CD, DVD, HD DVD and Blu-ray Discs. Most formats considered Black Book are formats used for video games or Digital Rights Management.
Black Book disc examples:
The audio side of a DualDisc (the video side is a standard DVD)
CD-based
NEC PC Engine (CD-ROM²)
Sega Saturn
Sega Dreamcast (GD-ROM)
DVD-based
The DVD-Video format itself is sometimes regarded as "black book" since it has no official rainbow book, despite being more standardized than other so-called "black book" formats.
Nintendo optical discs
Nintendo GameCube Game Disc (Nintendo GameCube)
Wii Optical Disc (Wii)
Xbox
Xbox 360
Blu-ray-based
Wii U Optical Disc (Wii U)
