Extended play (EP) is the name typically given to vinyl records or CDs which contain more music than a single, but are too short to qualify as albums. Usually, an EP has around 10–35 minutes of music, a single has up to 10 minutes and an album has 35–80 minutes. EPs were released in various sizes in different eras. In the 1950s and 1960s, EPs were typically 45 RPM recordings on 7" (18cm) discs, with two songs on each side.