"Rhythm changes" refer to a specific chord progression commonly used in jazz music, derived from the song "I Got Rhythm" by George Gershwin. The progression typically follows a 32-bar AABA form, where the A sections feature a series of major chords, while the B section introduces a contrasting set of chords, often with a minor feel. This chord structure has become a foundational element in jazz, inspiring countless compositions and improvisations. Musicians often use rhythm changes as a framework for solos, allowing for creative expression while adhering to a familiar harmonic pattern.