Compact Disc single

A CD single (sometimes abbreviated to CDS) is a music single in the form of a standard size compact disc. It is not to be confused with the Mini CD single, which uses a smaller form factor and has also been referred to as just a CD Single on some occasions. The format was introduced in the mid-1980s but did not gain its place in the market until the early 1990s. With the rise in digital downloads in the early 2010s, sales of CD singles have decreased.

Commercially released CD singles can vary in length from two songs (an A side and B side, in the tradition of 7" 45rpm records) up to six songs like an EP. Some contain multiple mixes of one or more songs (known as remixes), in the tradition of 12" vinyl singles, and in some cases, they may also contain a music video for the single itself as well as a collectible poster. Depending on the nation, there may be limits on the number of songs and total length for sales to count in singles charts.

Dire Straits' "Brothers in Arms" (1985) is reported to be the world's first CD single, issued in the UK in two separate singles as a promotional item, one distinguished with a logo for the tour, Live in '85, and a second to commemorate the Australian leg of the tour marked Live in '86. Containing four tracks, it had a very limited print run. CD singles were first made eligible for the UK Singles Chart in 1987, and the first number 1 available on the format in that country was "I Wanna Dance with Somebody (Who Loves Me)" by Whitney Houston in May 1987.

The Mini CD single format was originally created for use for singles in the late 1980s, but met with limited success, particularly in the US. The smaller CDs were more successful in Japan and have recently become more common in Europe, marketed as "Pocket" CD's for being small enough to fit in a shirt pocket. By 1989, the CD3 was in decline in the US (replaced by the 5-inch CD single, called CD-5).

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