2 Live Crew popularizes the Miami bass sound and scores a victory for free speech. The Geto Boys put Houston on the map, paving the way for UGK.

In the Bay Area, Too $hort channels pimp culture, MC Hammer becomes rap's first pop star, and Digital Underground introduces the world to Tupac Shakur.

KRS-One makes his mark at New York's legendary Latin Quarter club. A Tribe Called Quest and De La Soul cultivate an Afrocentric, jazzy style.

In the early 1990s, a new wave of hardcore East Coast artists emerges, led by Nas, Wu-Tang Clan and the Notorious B.I.G.

With the rise of N.W.A., gangsta rap and Suge Knight, the East Coast-West Coast rivalry climaxes with a lethal beef ensnaring the great Tupac Shakur.

In NYC, the Notorious B.I.G. fosters an empowering protégée, Lil' Kim. When the East-West feud claims Biggie, Puff Daddy and Jay-Z vie for the throne.

Alternative hip-hop bubbles up from the streets: Mos Def spits in NYC, the Freestyle Fellowship chops it up in LA, and Eminem battle on the circuit.

A hot, sticky music scene is born in Atlanta as the infectious hooks of TLC and Kris Kross yield to the gritty originality of OutKast and Goodie Mob.

Rooted in New Orleans's rich music culture, No Limit mogul Master P and bounce breakouts DJ Jimi and Juvenile shake rap and put twerking on the map.

Innovators explode out of the South: Houston's DJ Screw slows hip-hop down, Memphis's Three 6 Mafia goes dark, and Atlanta's Lil Jon brings the crunk.

Auteurs like the Neptunes' Pharrell and Chad expand the sonic palette. Timbaland and Missy Elliott lean forward. Kanye West and J Dilla reimagine rap.

Mixtapes spread the hottest sounds, infringe copyright and break artists. Among them, 50 Cent polarizes, T.I. takes off with trap, and Lil Wayne clicks.