The rhythm section of a jazz band consists of the drums, bass, and usually at least one instrument capable of playing chordss, such as a piano or guitar. The rhythm section is the foundation for the band; it sets the feel for the piece.
The horn section consists of wind instruments, which play the melody and main accompaniment. Typical horns found in a jazz band include the trumpet, saxophone, and trombone. The saxophones may also double on flute and clarinet.