Chord sequence
A♭m7 D♭7 G♭maj7
In every key
Four-note rootless voicings in their two forms, with the 3rd or the 7th on the bottom, played over the root.
Heard in Gb major
All the chords
The most common cadence in jazz: a ii-V resolving to the major 7th tonic.
Over Abm7 · ii7
Mode 2 of Major
Over Db7 · V7
Mode 5 of Major
Over Gbmaj7 · Imaj7
The major scale and its modes are the most commonly used scales in western music.