The 7-inch EP (for Extended Play) was a format introduced in 1952 by RCA Victor, just a few years after the introduction of the 7-inch single format in 1949. It sat between the 7-inch single and the 12-inch Long Play (LP) record, and like the 7-inch single it span at 45 rpm so could be played on any photograph with a 45 rpm setting.
By using narrower grooves, it was possible to squeeze 7½ minutes of playing time on each side at the expense of volume, allowing more than one song on each side (generally EPs have between three and six tracks). Like LPs, EPs did not necessarily have ‘title’ tracks, and could have different names to the songs on them (for example the 1963 Beatles EP simply called ‘The Beatles’ Hits’). They were also packaged more like an LP with a cardboard picture sleeve, whereas 7-inch singles until the 1970s generally had paper sleeves with just the record label on them.
Whilst less common in the US, the 7-inch EP was widely sold in the UK and some other European countries, and between 1960 and 1967 they were popular enough for Record Retailer magazine in the UK to compile a separate EP chart. They were a good way for artists to produce something more substantial than a single between LP releases.
They declined in popularity after the 1960s, and faced competition from formats such as 10-inch and 12-inch singles or EPs (which could allow for more sound volume with wider grooves), as well as Cassette and CD singles or EPs. However, small numbers of 7-inch EPs are still released.