The fugue is a musical form like the round, in which all the parts come in one after the other, playing the same melody. In the fugue, however, the answering part usually plays at either a fifth above or below.

Bach was the undisputed master of this art form, and his compositions in this genre range from simple ones like the “Little” fugue in g minor to huge works like the double fugue (two themes, both treated separately in sequence, then combined) in the “St. Anne” prelude & fugue in Eb major. His last composition was Contrapuctus XVIII from “Art of the Fugue” — a triple fugue where the last theme was his own name: BACH (Bb, A, C, B) in German note names).