In classical music there are, as the analytical programs tell us, first subjects and second subjects, free fantasias, recapitulations, and codas; there are fugues, with counter-subjects, strettos, and pedal points; there are passacaglias on ground basses, canons ad hypodiapente, and other ingenuities, which have, after all, stood or fallen by their prettiness as much as the simplest folk-tune.
Source: wiktionary