Digital audio storage

The DVD (common abbreviation for digital video disc or digital versatile disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kind of digital data and has been widely used to store video programs (watched using DVD players), software and other computer files. DVDs offer significantly higher storage capacity than compact discs (CD) while having the same dimensions. A standard single-layer DVD can store up to 4.7 GB of data, a dual-layer DVD up to 8.5 GB. Variants can store up to a maximum of 17.08 GB.

A CD single is a music single in the form of a compact disc (CD). Originally the CD single standard (as defined in the Red Book) was an 8 cm (3-inch) "mini CD" (CD3); later on the term referred to any single recorded onto a CD of any size, particularly the 12 cm (5-inch) "full-size" disc (CD5). From a technical viewpoint, a CD single is identical to any other audio CD. The format started gaining popularity in the early 1990s, but quickly declined in the early and mid 2000s, in favor of digital downloaded singles and CD albums.

The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. It uses the Compact Disc Digital Audio format which typically provides 74 minutes of audio on a disc. In later years, the compact disc was adapted for non-audio computer data storage purposes as CD-ROM and its derivatives. First released in Japan in October 1982, the CD was the second optical disc technology to be invented, after the much larger LaserDisc (LD). By 2007, 200 billion CDs (including audio CDs, CD-ROMs and CD-Rs) had been sold worldwide.

Mini CDs, or pocket CDs, are CDs with a smaller diameter and one-third the storage capacity of a standard 120 mm disc.

The DualDisc is a type of double-sided optical disc product developed by a group of record companies including MJJ Productions Inc., EMI Music, Universal Music Group, Sony BMG Music Entertainment, Warner Music Group, and 5.1 Entertainment Group and later under the aegis of the Recording Industry Association of America (RIAA). It featured an audio layer intended to be compatible with CD players (but too thin to meet Red Book CD specifications) on one side and a standard DVD layer on the other. In this respect it was similar to, but distinct from, the DVDplus developed in Europe by Dieter Dierks and covered by European patents.

Super Audio CD (SACD) is an optical disc format for audio storage introduced in 1999. It was developed jointly by Sony and Philips Electronics and intended to be the successor to the compact disc (CD) format.

High Definition Compatible Digital (HDCD) is a proprietary audio encode-decode process that claims to provide increased dynamic range over that of standard Compact Disc Digital Audio, while retaining backward compatibility with existing compact disc players.

DVD-Audio (commonly abbreviated as DVD-A) is a digital format for delivering high-fidelity audio content on a DVD. DVD-Audio uses most of the storage on the disc for high-quality audio and is not intended to be a video delivery format. DVD-Audio has much higher audio quality than most video DVDs containing concert films or music videos.

The Sony Multimedia CD-ROM Player was a portable CD-ROM–based multimedia player produced by Sony and released in 1992. It was used to run reference software, such as electronic publications and encyclopedia. Before its release, both Sony representatives and the press referred to the device as the Sony Bookman; that name remained in use in later publications.

DataPlay is an optical disc system developed by DataPlay Inc. and released to the consumer market in 2002. Using tiny (32mm diameter) disks enclosed in a protective cartridge storing 250MB per side, DataPlay was intended primarily for portable music playback. However, it could also store other types of data using pre-recorded disks and user-recorded disks (and disks that combined pre-recorded information with a writable area). It would also allow for multisession recording. DataPlay Inc. was founded in 1998 by Steve Volk. The company's namesake optical disc won the CES Best of Show award 2001.