Rock and roll developed out of country, blues, and R&B. Rock's exact origins and early influences have been hotly debated, and are the subjects of much scholarship. Though squarely in the blues tradition, rock took elements from Afro-Caribbean and Latin musical techniques. Rock was an urban style, formed in the areas where diverse populations resulted in the mixtures of African American, Latin and European genres ranging from the blues and country to polka and zydeco. Rock and roll first entered popular music through a style called "rockabilly", which fused the nascent sound with elements of country music. Black-performed rock and roll had previously had limited mainstream success, but it was the white performer Elvis Presley who first appealed to mainstream audiences with a black style of music, becoming one of the best-selling musicians in history, and brought rock and roll to audiences across the world.