Progressive rock (often shortened to "progressive", "prog rock" or "prog", also sometimes called, although not synonymous with, "art rock") is a form of rock music that evolved in the late 1960s and early 1970s as part of a "mostly British attempt to elevate rock music to new levels of artistic credibility".
Progressive rock bands pushed "rock's technical and compositional boundaries" by going beyond the standard rock or popular verse-chorus based song structures. Additionally, the arrangements often incorporate elements drawn from classical, jazz, and avant-garde music. Instrumental songs are more common, and songs with lyrics are sometimes conceptual, abstract, or based in fantasy. Progressive rock bands sometimes used "concept albums that made unified statements, usually telling an epic story or tackling a grand overarching theme".
Progressive rock developed from late-1960s psychedelic rock and jazz fusion, as part of a wide-ranging tendency in rock music of this era to draw inspiration from ever more diverse influences. The term came into most widespread use around the mid-1970s. While progressive rock reached the peak of its popularity in the 1970s and early 1980s, neo-progressive bands have continued playing for faithful audiences in the subsequent decades. Progressive rock sharply declined in popularity for much of the 1980s, but returned to prominence in the early-to-mid 1990s.