Chord progression
IV-V-I progression in the key of C major. The chords shown are F major, G major and C major. Play ( help · info ) A chord progression or harmonic progression is a succession of musical chords, which are two or more notes, typically sounded simultaneously. Chord progressions are the foundation of harmony in Western musical tradition from the common practice era of Classical music to the 21st century. Chord progressions are the foundation of Western popular music styles (e.g., pop music, rock music) and traditional music (e.g., blues and jazz). In these genres, chord progressions are the defining feature on which melody and rhythm are built. In tonal music, chord progressions have the function of establishing or contradicting a tonality, the technical name for what is commonly understood as the "key" of a song or piece. Chord progressions are usually expressed by Roman numerals in Classical music theory; for example, the common chord progression I vi/ii V7. In man...