Short answers, pulled from the story.
Hip-hop is widely dated to a back-to-school party on the 11th of August 1973, hosted by Cindy Campbell in the recreation room at 1520 Sedgwick Avenue in the Bronx, where her brother DJ Kool Herc ran the music. The genre emerged from block parties in the Bronx among African-American, Afro-Caribbean, and Latino communities in New York City.
The four principal elements of hip-hop are rapping, DJing, breakdancing, and graffiti art. Knowledge is sometimes described as a fifth element, underscoring its role in promoting empowerment and consciousness-raising through music.
The phrase hip hop has been in use since the 17th century, meaning a succession of hops, and appears in George Villiers's 1671 play The Rehearsal. In music it was popularized by DJs, with Lovebug Starsky claiming he coined it by 1979 after fumbling a change between records and chanting "a hip hop, hip hop" on the mic.
The Fatback Band's "King Tim III (Personality Jock)", released in March 1979 as the B-side to "You're My Candy Sweet", is generally considered the first commercially released rap song. The Sugarhill Gang's "Rapper's Delight" followed later in 1979 and became a Top 40 single that spread hip-hop across the country.
Hip-hop's golden age is the period after the genre became mainstream in 1986 until the mid-1990s, marked by increased diversity, innovation, and the expansion of hip-hop's influence. The deaths of Tupac Shakur on the 7th of September 1996, and the Notorious B.I.G. on the 9th of March 1997, are used as markers for the end of that era.
Hip-hop became the bestselling genre of popular music in the United States in 2017. On the 17th of July 2017, it was reported that hip-hop and R&B had overtaken rock as the most popular genre in music for the first time in U.S. history.
Hip-hop spread from the Bronx to nearly every country, taking root in places such as Cuba during the Special Period, Haiti from the early 1980s, Finland with the Blockfest in Tampere, and Toronto through the Toronto sound after Drake's success. Virtually all hip-hop artists worldwide acknowledge their debt to the Black and Latino people in New York who launched the movement.