Origins of rock and roll but it was used by the early 20th century, both to describe a spiritual fervor and as a sexual analogy. Various gospel, blues and swing recordings used the phrase before it became used more frequently – but still intermittently – in the late 1930s and 1940s, principally on recordings and in reviews of what became known as "rhythm and blues" music aimed at black audiences. In 1951, Cleveland-based disc jockey Alan Freed began playing this music style while popularizing the term "rock and roll" to describe it. Various recordings that date back to the 1940s have been named as the
Mobile disc jockey American Disc Jockey Awards Show was established, and its first edition was held in Las Vegas, Nevada. Since then, thirteen mobile DJs have been elected to the American Disc Jockey Hall of Fame. The thirteen members include John Rozz, Al Lampkin, Joe Martin, Robert A. Lindquist, Jon Michaels, Mike Buonaccorso, Sid Vanderpool, Bobby Morganstein, John Roberts, Ken Knotts, Ray "Ray Mar" Martinez, Cesar Cosio, and Bernie Howard-Fryman. The American Disc Jockey Awards Show annually recognizes and honors individuals who have given of themselves to benefit their community or a charitable cause in the name of the ADJA or the DJ