In popular air and jazz, modern notation almost always indicates only the central framework of the melody, harmony, or performance approach; musicians and singers are expected to know the performance conventions and styles associated with specific genres and pieces. For example, the "lead sheet" for a jazz tune may only indicate the melody Music For TV and the chord changes. The performers in the jazz ensemble are expected to know how to "flesh out" this necessary frame by adding ornaments, improvised music, and chordal accompaniment.

Music hypothesis encompasses the nature and mechanics of music. In a another complicated sense, hymn theory (in the western system) also distills and analyzes the no-frills of harmony – rhythm, harmony (harmonic function), melody, structure, and texture. People who study these properties are known as rock theorists.