Musical form began to become more structured and standardized during the Baroque Period.

Composers take a great deal of liberty with their forms, but (during the Baroque and Classical Periods especially) the general form of most pieces can be categorized under a few genera.

Here are some of the most important ones:

• Binary (A | B)
• Ternary (A | B | A)
• Rondo (A | B | A | C | A | B | A)
• Ritornello (A | B | A | C | A | D | A, etc.)
• Theme and Variations (A | A' | A'' | A''')
• Double Variation (A | B | A' | B' | A'' | B'')