The Velvet Rope

Rhythm and blues, often abbreviated to R&B, is a genre of popular African American music that originated in the 1940s. The term was originally... used by record companies to describe recordings marketed predominantly to urban African Americans, at a time when "urbane, rocking, jazz based music with a heavy, insistent beat" was becoming more popular. The term has subsequently had a number of shifts in meaning. From the early 1950s, the term rhythm and blues was frequently applied to blues records. Starting in the 1950s, after this style of music contributed to the development of rock and roll, the term "R&B" became used to refer to music styles that developed from and incorporated electric blues, as well as gospel and soul music. By the 1970s, rhythm and blues was used as a blanket term for soul and funk. In the 1980s, a newer style of R&B developed, becoming known as "Contemporary R&B". Jerry Wexler of Billboard magazine coined the term "rhythm and blues" in 1948 as a musical marketing term in the United States. It replaced the term "race music", which originally came from within the black community, but was deemed offensive in the postwar world.
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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 centred 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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