Binary form (AB)
A piece with two contrasting sections.
Ternary form (ABA)
A piece with three sections, the first returning.
Rondo form (ABACA)
A main theme keeps returning with contrasting sections.
Verse-chorus form
Alternating verses and choruses, common in pop music.
Coda
A section that brings a piece to an end.
Bridge
A contrasting section that links two parts of a song.
Introduction
The opening section of a piece.
Outro
The ending section of a piece.
Ground bass
A repeated bass line that forms the basis of a composition.