Scale
The E♭ major scale has 7 notes: E♭, F, G, A♭, B♭, C, D. Its enharmonic twin is D♯ major. Hear it, see it on the keyboard and find the chords that belong to it.
3 flats: B♭, E♭, A♭
Roman numerals show each chord's degree in the key. Upper-case is major, lower-case minor, ° diminished.
The major scale follows the step pattern W W H W W W H. It is the basis of Western tonal harmony, and every major key has a relative minor that shares its notes and key signature.
Use the Scale & Chord Finder to look up any other root or mode.