Y.E.S.

Yes didn't invent progressive rock, but they helped bring it to mainstream audiences, steering the development and definition of the genre. Once their classic lineup of Jon Anderson, Chris Squire, Steve Howe, Rick Wakeman, and Bill Bruford locked into place for 1971's Fragile, the band crystallized all of the sonic and visual signifiers that eventually became synonymous with prog rock. Yes shifted between complicated time signatures, spliced pastoral folk, and Baroque classical in their muscular rock & roll, structured their songs as mini-suites, and wrapped the entire package...