 Rock and roll music was first identified as a new genre in 1951 by Cleveland disc jockey Alan Freed who began playing this music style while popularizing the term "rock and roll" to describe it.By the mid-1950s, rock and roll emerged as a defined musical style in the United States, deriving most directly from the rhythm and blues music of the 1940s, which itself developed from earlier blues, boogie woogie, jazz, and swing music, and was also influenced by gospel, country and western, and traditional folk music.Freed's contribution in identifying rock as a new genre helped establish the Rock and Roll Hall of Fame, located in Cleveland.