The term "12-inch" usually refers to a single with several remixes. Now that advances in compact disc player technology have made the CD acceptable for mixing and "turntablism", the term maxi single is increasingly used.
In the mid-late 1980s, prior to the rise in popularity of the CD single, vinyl maxi-singles for popular artists often included "bonus" songs that were not included on albums, just as a 7" single included a B-side cut that was often not to be found on the referenced album. Many CD singles contain a number of such cuts, in a manner similar to the older EP vinyl format.
In the days of the 7″ single, and especially in R&B releases, the single would occasionally be "flipped" by radio DJs who found the B-side cut to be better for airplay than the intended A-side. One noteworthy example is the now-classic "I'll Be Around", the first of the Spinners' Thom Bell-produced hits for Atlantic Records in the mid-1970s. Around the time 12″ releases became standard for pop records, this practice faded, because of the increase in marketing costs, the reliance on video to sell single releases, and the public's expectation of quality packaging with photo or picture sleeves.
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