Ab Lydian scale on the guitar fretboard
The Ab Lydian scale is made of Ab (the root), Bb (major second), C (major third), D (augmented fourth), Eb (perfect fifth), F (major sixth) and G (major seventh). The fretboard shows every one of them across the neck in standard tuning (E A D G B E), and plays them back so you can hear the scale.
The Lydian mode is the fourth mode of the major scale, a major scale with a raised fourth. The raised fourth sits a tritone from the root, and the scale shares its notes with a major scale a fifth above. It is the brightest of the seven modes.