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Rock is a musical genre that developed during and after the 1950s. Its roots lie in rock and roll and rockabilly that emerged in the United States in the late forties and early fifties and which, in turn, evolved from blues, country music, and rhythm and blues.
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The rock sound revolves around the electric guitar or acoustic guitar and uses a strong backbeat established by the rhythm of the electric bass, drums, keyboard and other instruments such as the organ or piano. Along with the guitar or keyboard, the saxophone is used as a solo instrument.
Most rock groups consist of a vocalist, a guitarist, a bassist and a drummer.