chromaticism

thumb|right|300px|Chromatic fourth: lament bass bassline in Dm (D–C–C()–B–B–A)[[File:Lament bass.mid]] thumb|300px|The diatonic scale notes (above) and the non-scale chromatic notes (below)

Chromaticism is a compositional technique interspersing the primary diatonic pitches and chords with other pitches of the chromatic scale. In simple terms, within each octave, diatonic music uses only seven different notes, rather than the twelve available on a standard piano keyboard. Music is chromatic when it uses more than just these seven notes.