Rap pioneers the Sugarhill Gang (left to right: Wonder Mike, Master G and Big Bank Hank) perform live circa 1979. Michael Ochs Archives/Getty Images hide caption

Elizabeth Blair
Carole King, composing. Evening Standard/Getty Images hide caption
Al Green, from the cover of his Greatest Hits album, first released in 1975. Courtesy of the artist hide caption
Paul Williams, Eddie Kendricks, and David Ruffin of the Temptations, in 1965. Hulton Archive/Getty Images hide caption
Mama Cass Elliot with her Mamas and the Papas bandmates John Phillips and Denny Doherty in 1966. Express/Getty Images hide caption
Composer Richard Rodgers in London for the opening of 'The Boys From Syracuse'. Ted West/Getty Images hide caption