Chicago is an American rock band formed in 1967 in Chicago, Illinois. Known for blending rock and roll with horns, the group’s music incorporates elements of jazz, classical, R and B, and pop. Originally called The Big Thing, then the Chicago Transit Authority, they became simply Chicago in 1969. Early members included Peter Cetera, Terry Kath, Robert Lamm, Lee Loughnane, James Pankow, Walter Parazaider, and Danny Seraphine, with Cetera, Kath, and Lamm sharing vocals. Throughout decades of lineup changes, core members Lamm, Loughnane, and Pankow have remained with the band. Chicago’s commercial success includes over 100 million records sold worldwide, more than 40 million in the US alone, along with numerous gold, platinum, and multi-platinum albums. The group achieved five consecutive number one albums and twenty top ten singles on the Billboard charts. Their first album, Chicago Transit Authority, was inducted into the Grammy Hall of Fame, and the group itself has received a Grammy Award, a Grammy Lifetime Achievement Award, and induction into both the Rock and Roll Hall of Fame and the Songwriters Hall of Fame. Chicago is recognized as one of the most enduring and successful American rock bands.