Musical form: how pieces are organized.

1. Phrases and periods

A phrase is like a musical sentence. Many phrases last four or eight measures, but this is not a rule. A period is often made of two phrases: an antecedent phrase that sounds like a question and a consequent phrase that sounds like an answer.

2. Binary and ternary form

Binary form has two main sections: A and B. Ternary form has three sections: A-B-A. Ternary form is common when music presents an opening idea, moves to a contrasting middle, and returns to the opening.

3. Rondo and theme and variations

Rondo form keeps bringing back a main theme, often in a pattern like A-B-A-C-A. Theme and variations begins with a theme and then repeats it with changes in rhythm, texture, harmony, register, or character.

4. Sonata form preview

Sonata form is a larger structure common in classical sonatas, symphonies, and chamber music. It often includes exposition, development, and recapitulation. Because it is more detailed, it has its own deep-dive page.