Fig. 1 · C to D

interval

C major second

ClowerDupperM22 half steps

A whole step. The distance between most neighbouring notes of a major scale.

On the keyboard

CD
Fig. 2

What is true of it

C up a major second is D: 2 half steps, and 2 letters counting both ends.

Turn it upside down — put the C on top — and it becomes a minor seventh. The two numbers always add to nine, and the two sizes to twelve.

It is a dissonance.

Every interval on C

C → D♭minor second · dissonanceC → E♭minor third · imperfect consonanceC → Emajor third · imperfect consonanceC → Fperfect fourth · perfect consonanceC → F♯augmented fourth · dissonanceC → G♭diminished fifth · dissonanceC → Gperfect fifth · perfect consonanceC → A♭minor sixth · imperfect consonanceC → Amajor sixth · imperfect consonanceC → B♭minor seventh · dissonanceC → Bmajor seventh · dissonance

C♯ M2D♭ M2D M2D♯ M2E♭ M2E M2F M2F♯ M2all 204