According to Billboard chart statistics, Chicago is second only to the Beach Boys as the most successful American rock band of all time.

Chicago's roots can be traced back to DePaul University, when a gaggle of music students began playing a series of late-night jams at clubs around campus. The band featured several incredible instrumentalists, including saxophonist Walter Parazaider, trombonist James Pankow, and trumpet player Lee Loughnane, guitarist Terry Kath, keyboardist Robert Lamm, drummer Danny Seraphine, and bassist Peter Cetera (who was the last to join the original group).

The band released of their first record in early 1969 calling itself The Chicago Transit Authority.

Their eponymous debut was audacious to say the least. It was a sprawling double album that included jazzy explorations, extended jams with Latin percussion, and experimental, feedback-laden guitar work from the indomitable Terry Kath. The album received heavy airplay and gave us the hits "Does Anybody Really Know What Time It Is?" "Beginnings", and "Questions 67 and 68.

Soon after the album's release, the band's name was shortened to simply Chicago, when the actual Chicago Transit Authority threatened legal action.

The band's popularity exploded with their second album. Titled Chicago (aka Chicago II), was the group's breakthrough album. Make Me Smile," "Colour My World" and the searing "25 or 6 to 4" all come from this album.

Chicago began a blistering recording pace, releasing music at a rate of more than two LP discs per year through the 1970s.

Chicago was reborn in 1981 when producer David Foster, a new label (Warner Brothers), and new members joined the fray, while keyboardist/guitarist/singer Bill Champlin, guitarist Chris Pinnick; percussionist Laudir DeOliveira said goodbye.

Foster recruited in a cadre of top studio musicians for the Chicago 16 sessions, including the core members of Toto. Chicago returned to the top of the charts with "Hard to Say I'm Sorry/Get Away" and "Love Me Tomorrow."

Chicago's next album, titled Chicago 17, became the biggest selling album of the band's history. It featured "You're the Inspiration" and "Hard Habit to Break."

Peter Cetera left Chicago in 1985 and soon replaced by bassist/singer Jason Scheff, who joined the band for the final Foster-produced album Chicago 18.

In 1988 with Chicago 19, the band topped the charts again with the Diane Warren-penned single "Look Away."

In 1994, Chicago merged their unflappable sound with Big Band music by the likes of Sarah Vaughan, Glenn Miller, and Duke Ellington.

Chicago is still active four decades after its founding. Four of the six founding members (major songwriters Lamm and Pankow, plus Loughnane and Parazaider) are still members, as is Bill Champlin, Jason Scheff, Tris Imboden and Keith Howland.