A reaction to the cool school of jazz; bebop with a "back to the roots" ethos. It was bluesier and harder than the Brubeck/Getz stuff of Cool. Miles Davis' mid-50's quintet set the standard, but great music was abundant: Horace Silver, Clifford Brown and Max Roach, Art Blakey's Jazz Messengers, blowing sessions on labels like Blue Note and Prestige. Some gospel-tinged tunes were hits, paving the way for the soul jazz of the 60's.