A scale is a ladder of steps that gives a key its flavour. The major scale is the reference; start it on each of its seven degrees and you get the modes — same notes, different home, each with one characteristic tone that colours it (Lydian's ♯4, the Mixolydian ♭7, the Phrygian ♭2). Build any scale below, then see all seven parallel modes ranked bright to dark against the tonic you choose. For diatonic chords and melody harmonising, see the Chord & Scale Explorer.
All built on the same tonic (C), so the one altered degree that defines each mode stands out in colour.