<br>"A compilation album is an album (music or spoken-word) featuring tracks from one or multiple recording artists, often culled from a variety of sources (such as studio albums, live albums, singles, demos and outtakes.) The tracks are usually collected according to a common characteristic, such as popularity, source or subject matter. Many consider the term compilation album relevant only when there are numerous recording artists represented on an album; when the tracks are all essentially by the same artist, the album is often referred to as a retrospective album."
