Diatonic scale are major scales (those with a major third/triad: Ionian, Lydian, and Mixolydian), three are minor (those with a minor third/triad: Dorian, Phrygian, and Aeolian). To these may be added the seventh diatonic scale, with a diminished fifth above the reference note, the Locrian scale. These could be transposed not only to include one flat in the signature (as described by Glarean), but to all twelve notes of the chromatic scale, resulting in a total of eighty-four diatonic scales. The modern musical keyboard originated as a diatonic keyboard with only white keys. The black keys were progressively added for several purposes:
Bebop scale by modern practitioners of the bebop genre). The bebop dominant scale is derived from the Mixolydian mode and has a chromatic passing tone between the 7th and the root. \override Score.TimeSignature #'stencil = ##f \relative c' { </score> It has all the notes in both the major scale and the Mixolydian scale of the same root. This scale is often used over dominant seventh chords and all extended dominant chords, and the II-V chord progressions. According to Michael Miller, "[w]hen someone says they're playing 'the bebop scale,' this is the one they're talking about." The bebop Dorian scale (also known