This document discusses musical form and structure, specifically the AB form. It provides the examples of the songs "Yankee Doodle" and "Rocky Mountain" to illustrate the AB pattern. In AB form, a song has two sections (A and B) that repeat, such as verse and chorus. "Yankee Doodle" has an A section and B section that repeat in an AB pattern. "Rocky Mountain" demonstrates a repeating AB structure through two verses and two refrains.