Popular music of the late 20th century, especially among the younger population. Rock music originated in the 1950's in America, but swiftly became popular in Europe and throughout the world. In the late sixties and seventies, many British rock composers and performers became popular in the United States as well as in Europe. This style of music is characterized by a driving backbeat, electric guitar, and vocals. Rock music has been associated in the past with youth rebellion and protesting, but has developed into a more accepted form of entertainment among most age groups.