Bebop is a style of jazz music that originated during the 1940's. At that time, a number of young American musicians began experimenting with more complicated chord patterns and melodic ideas in a combo (small group) setting. These musicians included trumpeter Dizzy Gillespie, alto saxophonist Charlie Parker, pianists Bud Powell and Thelonious Monk, and drummers Kenny Clarke and Max Roach. The style they developed became known as bebop, or bop.