Modal jazz relied on modal scales instead of chords to create harmony.
Hard bop continued the bebop tradition but incorporated elements of blues, gospel, and rhythm and blues. Hard bop was characterised by medium tempos, expressive melodies, complex chords, and a warmer, more emotive sound. Art Blakey, Horace Silver, John Coltrane, and Sonny Rollins were notable musicians in this style. Modal jazz relied on modal scales instead of chords to create harmony. Modal jazz featured variable tempos, repetitive melodies, extensive improvisations, and a more spiritual and mystical sound. Key figures in this style included Miles Davis, John Coltrane, Bill Evans, and Herbie Hancock.