Short answers, pulled from the story.
Hip-hop culture originated in the South Bronx, New York City. The first documented indoor hip-hop party was held on the 11th of August 1973 at 1520 Sedgwick Avenue, organized by Cindy Campbell with her brother DJ Kool Herc as the DJ. Outdoor park jams organized by Disco King Mario of the Bronxdale Houses predate that event, and Kool Herc attended those as well.
Keith "Cowboy" Wiggins, a member of Grandmaster Flash and the Furious Five, is credited with coining the term in 1978. He scat-sang the syllables "hip" and "hop" to mimic the march of soldiers while teasing a friend who had joined the US Army, then worked the phrase into his stage performance. The term first appeared in print in a January 1982 interview of Afrika Bambaataa by Michael Holman in the East Village Eye.
The core elements of hip-hop culture are DJing and turntablism, MCing and rapping, breakdancing, and graffiti art. Beatboxing is considered a fifth element, grouped under the same pillar as DJing. Additional aspects include hip-hop language, hip-hop fashion, beatmaking and music production, and street entrepreneurship.
N.W.A's second album Niggaz4Life was the first gangsta rap album to enter the charts at number one. Ice-T is credited with recording what many consider the first gangsta rap single, "6 in the Mornin'", released in 1986. N.W.A's Straight Outta Compton, released in 1989, established West Coast hip-hop and drew a letter from FBI Assistant Director Milt Ahlerich over the song "Fuck tha Police".
A US district court judge ruled in June 1990 that 2 Live Crew's album As Nasty As They Wanna Be was obscene and illegal to sell. In 1992, the United States Court of Appeals for the Eleventh Circuit overturned that ruling. The Supreme Court of the United States declined to hear Broward County's appeal, effectively restoring the album's legal status.
The College Dropout, released in 2004, introduced the technique of speeding up or slowing down sampled source material, which became known as the "chipmunk soul sound." West's debut single "Through the Wire" used a sped-up sample from Chaka Khan's "Through the Fire" as a key example of the approach. The album sold over 4 million copies worldwide and was noted by critics for its innovative manipulation of samples drawn from pop culture.