Developed by inner-city African Americans back in 1970; hip hop music or also known by the name of rap music took almost a decade to get into American main stream world. By 1990, there had been notable artists be that Big Daddy Kane, or Kool G Rap. Basically, Keith Cowboy, rapper with Grandmaster Flash and Furious Five is credited to the creation. And then by 1990s, it turned down to 'gangsta' rap. DJs started getting job.