1. Sonata Form: This was the most common form used in classical music, especially for the first movement of symphonies, sonatas, and concertos. Sonata form consists of three main sections:
- Exposition: This section introduces the main themes of the movement and establishes the key relationships. It typically consists of two contrasting themes, presented in different keys.
- Development: This section explores and develops the thematic material from the exposition, often through modulation to different keys.
- Recapitulation: This section returns to the main themes from the exposition, presented in the original key. The development section may be omitted in some pieces.
2. Binary Form: This form was used for shorter, simpler movements, such as minuets and rondos. Binary form consists of two main sections:
- First section: This section introduces the main theme and establishes the key.
- Second section: This section presents contrasting material, often in a different key.
3. Rondo Form: This form was used for lively, dance-like movements, such as rondos and finales. Rondo form consists of a recurring refrain that alternates with contrasting episodes:
- Refrain: This section presents the main theme.
- Episodes: These sections present contrasting material, often in different keys.
4. Theme and Variations: This form was used for slower, more expressive movements, such as adagios and variations. Theme and variations consists of a main theme, which is then repeated several times with different variations:
- Theme: This section presents the main melody.
- Variations: These sections present embellished or modified versions of the theme.
5. Fugue: This form was used for contrapuntal movements, such as fugues and canons. Fugue consists of a main theme, called a subject, which is imitated and developed in different voices:
- Subject: This section introduces the main theme.
- Episodes: These sections present contrasting material, often in different keys.
- Recapitulation: This section returns to the subject, presented in the original key.