Hip hop as both a musical genre and a culture was formed during the 1970s when block parties became increasingly popular in New York City, particularly among African-American youth residing in the Bronx. However hip-hop music did not get officially recorded for the radio or television to play until 1979, largely due to poverty during hip-hop's birth and lack of acceptance outside ghetto neighborhoods.

[16] At block parties DJs played percussive breaks of popular songs using two turntables and a DJ mixer to be able to play breaks from two copies of the same record, alternating from one to the other and extending the "break".[17]

Hip hop's early evolution occurred as sampling technology and drum machines became widely available and affordable. Turntablist techniques such as scratching and beatmatching developed along with the breaks and Jamaican toasting, a chanting vocal style, was used over the beats. Rapping developed as a vocal style in which the artist speaks or chants along rhythmically with an instrumental or synthesized beat. Notable artists at this time include DJ Kool Herc, Grandmaster Flash and The Furious Five, Fab Five Freddy, Marley Marl, Afrika Bambaataa, Kool Moe Dee, Kurtis Blow, Doug E. Fresh, Whodini, Warp 9, The Fat Boys, and Spoonie Gee. The Sugarhill Gang's 1979 song "Rapper's Delight" is widely regarded to be the first hip hop record to gain widespread popularity in the mainstream.[18]

The 1980s marked the diversification of hip hop as the genre developed more complex styles. [19] Prior to the 1980s, hip hop music was largely confined within the United States. However, during the 1980s, it began to spread to music scenes in dozens of countries, many of which mixed hip hop with local styles to create new subgenres.