In the late 1960s, rock music was blended with folk music to create folk rock, blues to create blues-rock and with jazz, to create jazz-rock fusion, and without a time signature to create psychedelic rock. In the 1970s, rock incorporated influences from soul, funk, and latin music. Also in the 1970s, rock developed a number of subgenres, such as soft rock, heavy metal, hard rock, progressive rock, and punk rock. Rock subgenres that emerged in the 1980s included synthpop, hardcore punk and alternative rock. In the 1990s, rock subgenres included grunge, Britpop, indie rock, and nu metal.
A group of musicians specializing in rock music is called a rock band or rock group. Many rock groups consist of a guitarist, lead singer, bass guitarist, and drummer, forming a quartet. Some groups omit one or more of these roles and/or utilize a lead singer who plays an instrument while singing, forming a trio or duo; others include additional musicians such as one or two rhythm guitarists and/or a keyboardist. More rarely, groups also utilize stringed instruments such as violins or cellos, and/or horns like saxophones, trumpets or trombones. rock alternative rock classic rock indie rock hard rock punk rock progressive rock post-rock pop rock psychedelic rock blues rock folk rock gothic rock stoner rock garage rock j-rock glam rock soft rock southern rock post rock industrial rock rock n roll rock and roll art rock russian rock noise rock math rock space rock pop-rock christian rock