Hip-hop is a music genre that according to the people who created it, has sounds heredited from African roots.
It was developed in the early 1980's in the streets of the City Of New York as Rap. The people who created it attempted to incorporate positive messages into the sounds of Hip-hop and Rap.
Sadly as hip-hop evolved, it no longer included lyrics that were inspiring and positive to hear. Hip-hop included just about anything into their lyrics by the time the 90s hit, and by the end of the nineties; Hip-hop artists had incorporated into their songs the most vulgar, obscene, foul language lyrics than ANY other music genre in the history of the world.
That is the harsh way to put it, but even Hip-hop legends have to admit at one time or another that the recent change on Hip-hop has been for the worse:
"WireTap: "It's a black thing, you wouldn't understand."
JC: Yeah, or "God, this stuff is so violent and awful." Which I think is more common. So hip-hop criticism used to be conditioned in many cases by contextual issues, but these days it's not like that. It's more about the particular content without engaging that content's entire milieu. And that's a big shift. Which is interesting, because hip-hop began as an antidote to the excesses of formalism, and now we've come full circle. It's a bad development for hip-hop scholarship. But it gets me back to the point that Total Chaos, by centering the artists' voices, serves to put those kinds of critics in check. As you noted, polyculturalism is crucial. It may be easy to retreat into formalist deracination, but if you step away, as I argue in the introduction, from the frame that commodity capitalism provides for hip-hop, you see a very different picture." 
The topic has stirred up some issues and endangered the fame of many proffesionals and famous people like Oprah Winfrey:
"“My idea was, I want y’all to know that this is what’s going on,” Winfrey continued. “And I said to Ludacris, ‘A lot of people who listen to your music aren’t as smart as you are. So they take some of that stuff literally when you are just writing it for entertainment purposes.’”"