CD-ROM developed by Japanese company Denon in 1982. It was an extension of Compact Disc Digital Audio, and adapted the format to hold any form of digital data, with a storage capacity of 553 MiB. CD-ROM was then introduced by Denon and Sony at a Japanese computer show in 1984. The "Yellow Book" is the technical standard that defines the format of CD-ROMs. One of a set of color-bound books that contain the technical specifications for all CD formats, the "Yellow Book", standardized by Sony and Philips in 1983, specifies a format for discs with a maximum capacity of 650 MiB.
Philips Records the Philips Recording Center in Baarn, Netherlands, and formed Polyhymnia International (a recording and mastering company) and Pentatone Records (which specializes in SACD releases). Many of the Philips classical recordings have been reissued on the Eloquence label. Universal also released a "Philips 50" series marking the 50th anniversary of Philips Records in the early 2000s; some of those CDs are still in print. Pentatone has released Philips Quadraphonic sound recordings from the early and mid-1970s in 4-channel SACD format, as their RQR Series. Philips' classical catalog was issued on CD under the headings "Digital Classics", "Legendary Classics" and "Silver Line