Rock and roll of the late 1950s relied heavily upon 12-bar blues and 32-bar song forms. In the 1970s, rock developed a number of subgenres, such as soft rock, glam rock, heavy metal, hard rock, progressive rock, and punk rock. Did you know that group of musicians specializing in rock music is called a rock band or rock group. With a background including folk and jug band music, bands like the Grateful Dead and Big Brother & the Holding Company became two famous bands of the genre. Rock music is a loosely defined genre of popular music that developed during and after the 1960s. The first type of rock music, rock and roll, originated in the United States in the 1950s, and was largely derived from music of the American South. The primary instruments of early rock ‘n’ roll were guitar, bass, piano, drums, and saxophone. They were initially acclaimed for their energy and appealing individual personalities rather than for any innovations in their music, which was derived from Berry and Presley. Rock musicians today have the option of either conforming to the mainstream and hitting the big time or remaining in obscurity. For many rock bands, this means breaking away from themes of individuality and emotional detachment from society and singing more generally about love.