The circle of fifths (or Circle of 5ths) is a graphical representation of the relationships between the twelve pitches (or notes) in Western music that are separated by a perfect fifth interval. It is commonly used in music theory and composition as a tool for understanding and analyzing key signatures, chord progressions, and harmonic relationships.
The circle of fifths is arranged in a circular shape, with the twelve pitch names or key signatures evenly spaced around the circle. Starting from the top and moving clockwise, the pitches or key signatures are arranged in ascending order of fifths. This means that each pitch or key signature is a perfect fifth above the previous one. For example, if we start with the pitch or key of C, the pitch or key of G (a perfect fifth above C) would be next in clockwise direction, followed by D (a perfect fifth above G), and so on, until we complete the circle and arrive back at C.
The circle of fifths is a useful tool for understanding the relationships between different key signatures and their corresponding scales, as well as for identifying common chord progressions and modulations in music. It can also help musicians and composers with tasks such as transposing music to different keys, creating harmonic progressions, and understanding the relationships between chords within a particular key.