The 1980s were home to some of the most iconic moments in American history: the release of Michael Jackson’s “Thriller,” Sally Ride becoming the first American woman in space and the falling of the Berlin Wall. A currently dominant music style also owes its big break to the 1980s: rap.

According to ourpastimes.com, “Rapper’s Delight” by the Sugarhill Gang was the first rap record to play on mainstream radio in 1979. Following its release, rappers like N.W.A., Snoop Dogg and Biggie all made their mark with provocative lyrics about self-glorification and social issues.

Since rap was new at this time, all rappers were experimenting with different styles, including different speeds of beats and riffs. With the turn of the century, faster-style rapping became popular, with artists like Busta Rhymes, Twista and Eminem releasing songs in this style. As rap music evolved, lyrics became even faster, leading to the creation of mumble rap in the early 2010s.

Mumble rap is a genre characterized by melodic flows and lyrics that are mostly indecipherable, according to cleveland.com. Some of the most popular mumble rappers include Migos, Lil Pump and Playboi Carti.

Besides all being mumble rappers, they also all got their start on SoundCloud. SoundCloud is an online audio distribution platform and music sharing website that is easy to use and fairly inexpensive. Mumble rap can be conflated with “SoundCloud rap” as this genre started and spread there.

This rapping style has led to destruction of the lyricism used in the 80s and 90s. Those rappers created lyrics with a purpose  that were also coherent. Mumble rappers’ lyrics often make no sense, and are a series of disjointed words strung together, accompanied by a good beat.

Mumble rap has clearly been the next step in hip-hop’s evolution, but whether that step is progress or destruction of the genre is up for debate.