progressive rock
A rock genre that emerged in the late 1960s, characterized by extended compositions, complex arrangements, and the incorporation of classical and jazz elements.
In Depth
Progressive rock, or prog, grew from the ambition of rock musicians to transcend the three-minute pop single format and create music of greater complexity and artistic scope. Bands like King Crimson, Yes, Genesis, Emerson Lake & Palmer, and Pink Floyd drew on classical music's structural sophistication, jazz's improvisational freedom, and electronic music's timbral possibilities to create expansive works that could fill entire album sides.
The genre's hallmarks include unusual time signatures, virtuosic instrumental technique, concept albums with unified themes, and the use of then-novel instruments like the Mellotron, Moog synthesizer, and Hammond organ. After a commercial peak in the mid-1970s, prog faced a backlash from punk rock's stripped-down ethos but never disappeared, evolving through neo-prog, progressive metal, and math rock, while its influence pervades modern art rock and experimental music.
Yes's Tales from Topographic Oceans (1973) is a double album containing only four tracks — one per side — each approximately 20 minutes long.