a genre of popular music originating in the 1950s; a blend of black rhythm-and-blues with white country-and-western
"rock is a generic term for the range of styles that evolved out of rock'n'roll."
A broad genre of popular music, including especially those styles ultimately derived from rock and roll, employing electrical amplification, heavy use of guitars, 4/4 time with strong percussive rhythm on beats two and four (backbeat), and usually themes of bold wildness, rebellion, and sexuality.