An extended play (EP) is a musical recording that contains more tracks than a single but fewer than an album or LP record. Contemporary EPs generally contain four to five tracks, and are considered "less expensive and time-consuming" for an artist to produce than an album. An EP originally referred to specific types of records other than 78 rpm standard play (SP) and LP, but it is now applied to mid-length CDs and downloads as well. In K-pop they are usually referred to as mini albums. Ricardo Baca of The Denver Post said, "EPs—originally extended-play 'single' releases that are shorter than traditional albums—have long been popular with punk and indie bands." In the United Kingdom, the Official Chart Company defines a boundary between EP and album classification at 25 minutes of maximum length and no more than four tracks (not counting alternative versions of featured songs, if present).
Background
History
EPs were released in various sizes in different eras. The earliest multi-track records, issued around 1919 by Grey Gull Records, were vertically cut 78 rpm discs known as "2-in-1" records. These had finer than usual grooves, like Edison Disc Records. By 1949, when the 45 rpm single and 33 rpm LP were competing formats, seven-inch 45 rpm singles had a maximum playing time of only about four minutes per side.

Partly as an attempt to compete with the LP introduced in 1948 by rival Columbia, RCA Victor introduced "Extended Play" 45s during 1952. Their narrower grooves, achieved by lowering the cutting levels and sound compression optionally, enabled them to hold up to 7.5 minutes per side—but still be played by a standard 45rpm phonograph. In the early era, record companies released the entire content of LPs as 45rpm EPs. These were usually 10-inch LPs (released until the mid-1950s) split onto two seven-inch EPs or 12-inch LPs split onto three seven-inch EPs, either sold separately or together in gatefold covers. This practice became much less common with the advent of triple-speed-available phonographs.

Introduced by RCA in the US in 1952, EMI issued the first EPs in Britain in April 1954. EPs were usually compilations of singles or album samplers and were typically played at 45 rpm on seven-inch (18cm) discs, with two songs on each side. RCA had success in the format with their top money earner, Elvis Presley, issuing 28 Elvis EPs between 1956 and 1967, many of which topped the separate Billboard EP chart during its brief existence. Other than those published by RCA, EPs were relatively uncommon in the United States and Canada, but they were widely sold in the United Kingdom, and in some other European countries, during the 1950s and 1960s. In Sweden EP was for long the most popular record format, with as much as 85% of the market in the late 1950s being EPs.

Billboard introduced a weekly EP chart in October 1957, noting that "the teen-age market apparently dominates the EP business, with seven out of the top 10 best-selling EP's featuring artists with powerful teen-age appeal — four sets by Elvis Presley, two by Pat Boone and one by Little Richard". Record Retailer printed an EP chart in 1960. The New Musical Express (NME), Melody Maker, Disc and Music Echo and the Record Mirror continued to list EPs on their respective singles charts. When the BBC and Record Retailer commissioned the British Market Research Bureau (BMRB) (now: Kantar Group) to compile a chart, it was restricted to singles, and EPs disappeared from the listings.
The popularity of EPs in the US had declined in the early 1960s in favor of LPs. In the UK Cliff Richard and the Shadows, both individually and collectively, and the Beatles were the most prolific artists issuing EPs in the 1960s, many of them highly successful releases. The Beatles' Twist and Shout outsold most singles for some weeks in 1963. The success of the EP in Britain lasted until around 1967, but it later had a strong revival with punk rock in the late 1970s and the adaptation of the format for 12" and CD singles.
In Britain EPs were sometimes used to repackage songs that had previously been issued on albums. The Shadows released EPs The Shadows No. 2 and The Shadows No. 3 both of which included songs found on The Shadows album. The songs from Adam Faith's first album were also released on three EPs, all of which had the same cover as the album, but listed the tracks on the top. The Beatles EP Twist and Shout contained only songs found on their Please Please Me album.





