circle of fifths

Relationship among the 12 tones of the chromatic scale, their corresponding key signatures, and the associated major and minor keys;geometrical representation of relationships among the 12 pitch classes of the chromatic scale in pitch class space

In music theory, the circle of fifths is a way of organizing the 12 chromatic pitches as a sequence of perfect fifths. If C is chosen as a starting point, the sequence is: C, G, D, A, E, B, F♯, C♯, A♭, E♭, B♭, F. Continuing the pattern from F returns the sequence to its starting point of C. This order places the most closely related key signatures adjacent to one another. It is usually illustrated in the form of a circle.