Then came Macarena (Los del Río, 1995)—a song critics loved to hate, but which spent 14 weeks at #1. Any credible list of the 100 greatest 90s songs must include it, not for artistry, but as a monument to the decade’s love of goofy, unifying dance crazes.

If one song started the 90s as we remember them, it’s Nirvana’s Smells Like Teen Spirit (1991). Released on Nevermind , it didn’t invent grunge, but it murdered the excess of 80s rock overnight. Within a year, lists of the greatest songs had to make room for Pearl Jam’s Alive , Soundgarden’s Black Hole Sun , and Alice in Chains’ Rooster . But grunge wasn’t alone. Dr. Dre’s Nuthin’ but a ‘G’ Thang (1992) introduced G-funk, proving that West Coast hip-hop would define the decade’s street sound. Meanwhile, Sinead O’Connor’s Nothing Compares 2 U (1990) showed that a bald Irish woman with a Prince-penned ballad could break everyone’s heart.

As the decade closed, two seismic shifts occurred. First, Backstreet Boys and *NSYNC perfected the boy-band ballad ( I Want It That Way , 1999), while Britney Spears’ …Baby One More Time (1998) blended teen pop with a Max Martin production that predicted the 2000s. Second, hip-hop went mainstream-mega: Lauryn Hill’s Doo Wop (That Thing) (1998) won five Grammys, and Eminem’s My Name Is (1999) arrived just as the list-makers were finalizing their votes.