An EP (short for extended play) is a musical recording that contains more music than a single, but is usually too short to qualify as a full studio album or LP. The term EP originally referred to specific types of vinyl records other than 78 rpm standard play (SP) records and LP records, but it is now applied to mid-length compact discs and music downloads as well. 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 length or four tracks (not counting alternative versions of featured songs, if present).