Mary Chapin Carpenter

Folk music includes both traditional music and the genre that evolved from it during the 20th century folk revival. The term originated in the 19th... century but is often applied to music that is older than that. Certain types of folk music are also called world music. Traditional folk music has been defined in several ways: as music transmitted by mouth, as music of the lower classes, and as music with unknown composers. It has been contrasted with commercial and classical styles. One meaning often given is that of old songs, with no known composers; another is music that has been transmitted and evolved by a process of oral transmission or performed by custom over a long period of time. Starting in the mid-20th century a new form of popular folk music evolved from traditional folk music. This process and period is called the folk revival and reached a zenith in the 1960s. The most common name for this new form of music is also "folk music", but is often called "contemporary folk music" or "folk revival music" to make the distinction. This type of folk music also includes fusion genres such as folk rock, folk metal, electric folk, and others.
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Rock music is a genre of popular music that developed during and after the 1960s, 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 with a 4/4 beat 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.
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