The following example uses the very popular AABA form. Section A is usually 8 bars long and repeated, followed by an 8 bar contrasting B section and finally finishes on the last 8 bar A section. In this example, all sections are written out individually to demonstrate more variety. This chord progression is commonly referred as the rhythm changes. In the first A only chord notes are being used, the second and last A utilize chromatic notes and section B is based around the mixolydian modes.