DurTonarten

DurTonarten are the major keys in Western tonal music. In music theory, a major key is defined by its tonic note and the corresponding major scale, which follows the interval pattern whole, whole, half, whole, whole, whole, half. The tonic is the most stable pitch around which melodies and harmonies revolve.

Notation and key signatures are the primary means of identifying DurTonarten. Each major key has a key signature consisting of sharps or flats. The order of sharps is F, C, G, D, A, E, B; the order of flats is B, E, A, D, G, C, F. For example, C major has no sharps or flats, G major has one sharp (F#), and F major has one flat (Bb). The circle of fifths shows how keys relate to one another by moving in intervals of a fifth, with sharps accumulating as you move clockwise and flats as you move counterclockwise.

Enharmonic equivalents exist among DurTonarten. Some keys sound identical but are spelled differently, such as C# major and Db major, which are enharmonically equivalent. C# major requires seven sharps while Db major uses five flats; in practice, composers choose spellings that suit notation and instrument considerations.

DurTonarten also relate to minor keys through the concept of relative keys: each major key has a relative minor located a minor third below the tonic, sharing the same key signature (for example, C major and A minor).

Historically and in common practice, DurTonarten underpin tonal harmony, modulation, and form, influencing composition, analysis, and pedagogy.