A minor scale is a ladder of notes that begins with a minor 3rd interval between the tonic and the 3rd degree of the scale. Because of this interval the scale has greater harmonic complexity that its brother the major scale and because of this is perceived as having a sad or blue or cool quality. There are a number of minor scale sounds in popular use including, Dorian, Harmonic, Melodic, Jazz Melodic, Phrygian, Spanish Phrygian, Aeolian, Pentatonic, Blues.