Rock music is a genre of popular music that originated as "rock and roll" in the United States in the 1950s, 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 blues, rhythm and blues and country music. Since the term rock began to be used in preference to rock and roll from the late-1960s, it has often been contrasted with pop music, with which it has shared many characteristics, but from which it is often distanced by an emphasis on musicianship, live performance and a focus on serious and progressive themes as part of an ideology of authenticity that is frequently combined with an awareness of the genre's history and development. According to Simon Frith "rock was something more than pop, something more than rock and roll. and, in musical terms, it is essentially conservative". and, in musical terms, it is essentially conservative". Rock music also drew strongly on a number of other genres such as electric blues and folk, and incorporated influences from jazz, classical and other musical sources.
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. Similarly, 1970s punk culture spawned the visually distinctive goth and emo subcultures. From about 1967 the term was increasingly used in opposition to the term rock music, a division that gave generic significance to both terms. Whereas rock aspired to authenticity and an expansion of the possibilities of popular music, pop was more commercial, ephemeral and accessible. According to Simon Frith pop music is produced "as a matter of enterprise not art", is "designed to appeal to everyone" and "doesn't come from any particular place or mark off any particular taste".
Rock musicians combined an emphasis on skill and technique with the romantic concept of art as artistic expression, original and sincere". In the new millennium the term rock has sometimes been used as a blanket term including forms such as pop music, reggae music, soul music, and even hip hop, with which it has been influenced but often contrasted through much of its history.. By the late 1960s, referred to as the "golden age" or "classic rock" period, a number of distinct rock music subgenres had emerged, including hybrids like blues rock, folk rock, country rock, raga rock, and jazz-rock fusion, many of which contributed to the development of psychedelic rock, which was influenced by the countercultural psychedelic scene. since the late 1950s, however, pop has had the special meaning of non-classical mus[ic], usually in the form of songs, performed by such artists as the Beatles, the Rolling Stones, ABBA, etc". Grove Music Online also states that "… since the late 1950s, however, pop has had the special meaning of non-classical mus[ic], usually in the form of songs, performed by such artists as the Beatles, the Rolling Stones, ABBA, etc". Grove Music Online also states that "… It is "not driven by any significant ambition except profit and commercial reward … Harmonies range from the common triad to parallel fourths and fifths and dissonant harmonic progressions. Rock songs, since the late 1950s and particularly from the mid-1960s onwards, often used the verse-chorus structure derived from blues and folk music, but there has been considerable variation from this model. Critics have stressed the eclecticism and stylistic diversity of rock. Because of its complex history and tendency to borrow from other musical and cultural forms, it has been argued that "it is impossible to bind rock music to a rigidly delineated musical definition. It has also made use of technological innovation. According to Grove Music Online, the term "pop music" "originated in Britain in the mid-1950s as a description for rock and roll and the new youth music styles that it influenced …". The Oxford Dictionary of Music states that while pop's "earlier meaning meant concerts appealing to a wide audience … Pop is not a do-it-yourself music but is professionally produced and packaged".