If “25 Or 6 To 4” doesn’t get you shakin’ your tail feather, rock and roll just might not be for you — or at least the Chicago brand of rock. In a 2009 interview, founding Chicago member David Lamm said, “Some of the guys in Earth, Wind & Fire said to me, ‘I know you were doing acid when you wrote that song!” (He also denied that acid had anything to do with it.) A song about writing a song, “25 Or 6 To 4” showed up on the eponymously named album Chicago, (sometimes referred to as Chicago II) after the band was forced to shorten their name from Chicago Transit Authority to simply Chicago. Starting out as the opening act for rock and roll legends Jimi Hendrix and Janis Joplin, Chicago rose to fame through the 1970s with their blend of jazz fusion and rock that would eventually earn them a position in the Rock and Roll Hall of Fame. With nearly a half century of shows under their belt, Chicago remains one of the longest-running rock and roll acts in the history of the genre.