In music theory, the minor scale is three scale patterns – the natural minor scale (or Aeolian mode), the harmonic minor scale, and the melodic minor scale (ascending or descending) – rather than just two as with the major scale, which also has a harmonic form but lacks a melodic form.
In each of these scales, the first, third, and fifth scale degrees form a minor triad (rather than a major triad, as in a major scale). In some contexts, minor scale is used to refer to any heptatonic scale with this property.