Melodic organization

Motif (motive)

A melodic idea that might be repeated throughout a piece, similar to a theme but on a smaller scale

Theme

The melodic figure that serves as the basis of composition

Can be just about anything

Phrase

A portion of a composition with distinct endpoints and concluding with a cadence—usually is a part of a period

Period

Usually composed of 2 phrases, a period is a musical structure in which the first phrase sets up a musical idea and the second phrase resolves the idea

Contrasting vs. parallel periods

Contrasting periods begin differently and thus follow different structures, while parallel ideas build differently upon the same initial idea

Double period

Contains at least 4 phrases, commonly with the first period concluding with a weak cadence as the second with a song

Phrase group

A phrase group is functionally similar to a period, but ends in a half cadence rather than a strong conclusion that would signal the end of a period

Sequence

A musical idea repeated with variations in pitch, following a pattern

Real vs. tonal sequences

A real sequence maintains the exact intervals between notes while a tonal sequence adjusts the pitches to fit the key

False sequence

Part of the sequence is repeated without variation while the other part follows the sequence

Modified sequence

Modified sequences are altered or embellished in some way that does not break the sequence by changing the melody or rhythm entirely