There is perhaps no issue in 2017 hip-hop more divisive than the merits of so-called “mumble rap.” The term, which is now applied to a wide swath of new artists with different styles, originated as a way to describe artists like Future and Young Thug, whose lyrics are often initially tough to decipher. However, the tradition of focusing on melody and flow over lyrical articulation goes back much further to artists like Bone Thugs-n-Harmony, Ol' Dirty Bastard, and more. Today, “mumble rappers” like Lil Uzi Vert, 21 Savage, and the aforementioned Future rule the charts, and even traditional MCs are taking notice, for better or for worse.

Check out the video above to learn more about the history and rise of mumble rap.