Blue Book (CD standard) Blue Book (CD standard) The Blue Book is a compact disc standard developed in 1995 by Philips and Sony. It defines the Enhanced Music CD format (E-CD, also known as CD-Extra, CD-Plus and CD+), which combines audio tracks and data tracks on the same disc. The format was created as a way to solve the problem of mixed mode CDs, which were not properly supported by many CD players. The standard is not freely available and must be licensed from Philips. E-CDs are created through the "stamped multisession" technology, which creates two sessions on a disc. The first session of
CD-R the cost of typical recorders was down to $10,000–12,000, and in September 1995, Hewlett-Packard introduced its model 4020i manufactured by Philips, which, at $995, was the first recorder to cost less than $1000. The dye materials developed by Taiyo Yuden made it possible for CD-R discs to be compatible with Audio CD and CD-ROM discs. Initially, in the United States, there was a market separation between "music" CD-Rs and "data" CD-Rs, the former being several times more expensive than the latter due to industry copyright arrangements with the RIAA. Physically, there is no difference between the discs save for the