The seven modes, one by one

Each mode has a formula, a colour and one note that makes it recognisable. Compare each with the major scale on the same tonic and the differences become easy to hear.

The formulas

The seven modes compared with the major scale on the same tonic, from brightest to darkest. The characteristic note is in bold.
Mode	Formula	Quality	Characteristic note
Lydian	1 2 3 ♯4 5 6 7	major	♯4
Ionian	1 2 3 4 5 6 7	major	(reference)
Mixolydian	1 2 3 4 5 6 ♭7	major	♭7
Dorian	1 2 ♭3 4 5 6 ♭7	minor	major 6
Aeolian	1 2 ♭3 4 5 ♭6 ♭7	minor	♭6
Phrygian	1 ♭2 ♭3 4 5 ♭6 ♭7	minor	♭2
Locrian	1 ♭2 ♭3 4 ♭5 ♭6 ♭7	diminished	♭5

The order goes from brightest to darkest, and each step lowers exactly one note: Lydian → Ionian (♯4 → 4); Ionian → Mixolydian (7 → ♭7); Mixolydian → Dorian (3 → ♭3); Dorian → Aeolian (6 → ♭6); Aeolian → Phrygian (2 → ♭2); Phrygian → Locrian (5 → ♭5). This is the modal brightness of each mode.

Major modes have a major 3rd: Ionian, Lydian, Mixolydian. Minor modes have a ♭3: Dorian, Aeolian, Phrygian, plus Locrian, which also has a ♭5.

The characteristic note

The characteristic note is the one to emphasise to make a mode recognisable. Without it the mode sounds like plain major or minor.

Typical uses, as tendencies: Mixolydian in blues, rock and funk over dominant chords; Dorian in funk, soul, jazz and many folk tunes; Phrygian in flamenco-flavoured and metal music; Lydian in film music and some jazz; Locrian mainly over the m7♭5 chord.

All seven from the same root

Each shape below starts from C at fret 3 on the A string. Only the notes that change are renamed; compare each one with Ionian.