Rock n Roll orignated in the major southern cities of the Unites States during the 1940’s and 1950’s and expanded to northern and western cities as well as European cities by the end of the 1950’s.
The sound of early Rock n Roll is a combination of Jump blues, electric guitars and shouting vocals. Rock n Roll music is usually focused on the lead instrument of the guitar, or in some cased the piano (Jerry Lee Lewis and Little Richard). It has a backbeat that is accented by the snare drum. An early Rock n Roll band would typically consist of guitar, drums and bass with additions of a boogie woogie piano and horns. The music is focused on creating a rhythm for dancing.
Another defining factor of Rock n Roll is a wild stage performance, signature moves, feeling of rebellion or danger, and a fun sense of humor.