Ternary form can be used to organize a small section of a longer piece, one movement of a multi-movement piece, or an entire piece of music. It organizes the music into three sections:
First, there is the A-section that begins the piece.
Next, there is the middle B-section that is significantly different.
The final section of ternary form is the return of the A-section, where we hear the same or very similar music to the beginning of the piece.