The underground mixtape has long been a staple in hip-hop, with blended DJ selections being all the rage throughout the '90s. But this decade saw the format mutate: Rappers began to take matters into their own hands, working directly with DJs to create artist-specific tapes of original material. As the format shifted to a digital medium, the "mixtape" became shorthand for releases that were neither mixed nor tapes. These days, mixtape DJs rarely blend or scratch on their tapes, and instead play more of a host's role — which usually entails them shouting the artist's name loudly or overdubbing the sound of explosions.
Distributed through semi-official means — such as street-corner bootleggers and, later, shared MP3s — the artist-oriented mixtape has just about fully supplanted the album as the definitive full-length form in hip-hop. Some of this year's biggest rap singles found their footing on mixtapes, including Drake's "Successful" and "Best I Ever Had" and Gucci Mane's "Wasted," to name a few. Many up-and-comers aren't even eying deals anymore, instead touring solely off of tape buzz. Make no mistake: The future of the genre lies not in the hands of the industry, but at your corner bootlegger or favorite blog. Here's a look back at some of the decade's most memorable tapes.