The document provides a comprehensive guide to hip-hop music groups, exploring their history, characteristics, and notable examples. It discusses how early groups like Grandmaster Flash and the Furious Five helped establish hip-hop. Iconic 1980s and 1990s groups like Run-DMC, Public Enemy, and N.W.A. helped define the genre's sound and identity. The collaborative nature of groups is defined by MCs, DJs, and other roles working together with interplay and intricate rhymes. Notable groups highlighted include Run-DMC, Wu-Tang Clan, Outkast, The Roots, and A Tribe Called Quest.