Rock music is a genre of
popular music that originated as "
rock and roll"
in 1950s America and developed into a range of different styles in the
1960s and later, particularly in the United Kingdom and the United
States. It has its roots in 1940s' and 1950s' rock and roll, itself heavily influenced by
rhythm and blues and
country music. Rock music also drew strongly on a number of other genres such as
blues and
folk, and incorporated influences from
jazz,
classical and other musical sources.
Musically, rock has centered around the
electric guitar, usually as part of a
rock group with
bass guitar and
drums. Typically, rock is song-based music usually with a
4/4 time signature utilizing a
verse-chorus form, but the genre has become extremely diverse and common musical characteristics are difficult to define. Like
pop music,
lyrics often stress romantic love but also address a wide variety of
other themes that are frequently social or political in emphasis. The
dominance of rock by white, male musicians has been seen as one of the
key factors shaping the themes explored in rock music. Rock places a
higher degree of emphasis on musicianship, live performance, and an
ideology of authenticity than pop music.
By the late 1960s, referred to as the "golden age" or "classic rock" period, a number of distinct rock music sub-genres had emerged, including hybrids like
blues rock,
folk rock,
country rock, and
jazz-rock fusion, many of which contributed to the development of
psychedelic rock influenced by the
counter-cultural psychedelic scene. New genres that emerged from this scene included
progressive rock, which extended the artistic elements;
glam rock, which highlighted showmanship and visual style; and the diverse and enduring major sub-genre of
heavy metal, which emphasized volume, power, and speed. In the second half of the 1970s,
punk rock
both intensified and reacted against some of these trends to produce a
raw, energetic form of music characterized by overt political and social
critiques. Punk was an influence into the 1980s on the subsequent
development of other sub-genres, including
New Wave,
post-punk and eventually the
alternative rock movement. From the 1990s alternative rock began to dominate rock music and break through into the mainstream in the form of
grunge,
Britpop, and
indie rock. Further fusion sub-genres have since emerged, including
pop punk,
rap rock, and
rap metal, as well as conscious attempts to revisit rock's history, including the
garage rock/
post-punk and
synthpop revivals at the beginning of the new millennium.
Rock music has also embodied and served as the vehicle for cultural
and social movements, leading to major sub-cultures including
mods and
rockers in the UK and the
hippie counterculture that spread out from San Francisco in the US in the 1960s. Similarly, 1970s
punk culture spawned the visually distinctive
goth and
emo subcultures. Inheriting the folk tradition of the
protest song,
rock music has been associated with political activism as well as
changes in social attitudes to race, sex and drug use, and is often seen
as an expression of youth revolt against adult
consumerism and conformity.