"That's a rough, rugged and raw..." This song single-handedly invented "new jack swing" for the masses. If you weren't trying to do the running man to this bassline, were you even alive in 1990?

1990 was a musical fork in the road. On one side, the shiny, synth-driven pop of the late ‘80s was still holding court. On the other, grunge was sharpening its axes in Seattle, and hip-hop was becoming the voice of a new generation. It was the year of the Vanilla Ice high-top fade, the MC Hammer parachute pants, and the birth of the power ballad that could bring a stadium to tears.

Stop! Hammer time. You couldn't go to a wedding, a roller rink, or a school dance without hearing this sample-laden (Rick James, anyone?) hip-hop smash. The pants were ridiculous, but the beat was undeniable.

The arrival of a legend. When Mariah hit those whistle tones at the end of this song, the music industry stopped. Every singer since has been trying to replicate this debut.

The boy band craze was at its absolute peak. NKOTB told us to take it "step by step," and millions of screaming teenage girls happily obliged.

1990 didn't know what the rest of the decade would bring (Nirvana was just around the corner). It was simply having a really, really good time dancing in parachute pants.