Hip hop is a cultural movement, of which music is a part, along with graffiti and breakdancing. The music is composed of two parts, rapping, the delivery of swift, highly rhythmic and lyrical vocals, and DJing, the production of instrumentation either through sampling, instrumentation, turntablism or beatboxing. Hip hop arose in the early 1970s in The Bronx, New York City. Jamaican immigrant DJ Kool Herc is widely regarded as the progenitor of hip hop; he brought with him the practice of toasting over the rhythms of popular songs. In New York, DJs like Kool Herc played records of popular funk, disco and rock songs. Emcees originally arose to introduce the songs and keep the crowd excited and dancing; over time, the DJs began isolating the percussion breaks (the rhythmic climax of songs), thus producing a repeated beat that the emcees rapped over.