moreover, if we draw all seven diatonic modes we can see them all as rotations of the ionian mode. note also the significance of the 6 o'clock point. this corresponds to a tritone. the modes including pitches a tritone from the tonic (locrian and lydian) are least used. the 5 o'clock and 7 o'clock pitches are also important points corresponding to a perfect fourth and perfect fifth respectively. the most used scales/modes - major (ionian mode), minor (aeolian mode) and mixolydian - include these pitches.