AABA form
A 32-bar song form consisting of four 8-bar sections: two statements of the theme, a contrasting bridge, and a return
In Depth
AABA form dominated American popular song from the 1920s through the 1950s and remains the structure of most jazz standards. The A sections present the main melody and harmonic progression; the B section (the bridge or middle eight) provides contrast in melody, harmony, and often key. The final A section returns to the opening material, sometimes with a modified ending. The form's balance of repetition and contrast makes it ideal for both composition and improvisation.
Over the Rainbow, I Got Rhythm, Body and Soul, and All the Things You Are are all AABA form — the structure behind the Great American Songbook.