Country music (or country and Western) is a blend of traditional and popular musical forms traditionally found in the Southern United States and the Canadian Maritimes that evolved rapidly in the 1920s. Country music has produced two of the top selling solo artists of all time. Elvis Presley, who was known early on as �the Hillbilly Cat� and was a regular on the radio program Louisiana Hayride, went on to become a defining figure in the emergence of rock and roll. Contemporary musician Garth Brooks, with 128 million albums sold, is the top-domestic-selling solo U.S. artist in U.S. history.