I went to my prom wearing a V-neck dress of black gauze, and it wasn’t until I looked at pictures taken by my boyfriend’s mom that I realized — oops! — I’d slipped a bit of a nip. If kindly Mrs. Coker ever noticed, she never said a word. But her son and I laughed about it until we cried (or at least I did).

I’ve often sought a metaphor in that experience, because that’s just how prom is. It mythologizes itself: in Hollywood movies, in elaborate promposals, in dewy glam-ups. The thing itself can never live up to our dreams of what it could be, and yet the dream persists — a sentence that describes prom as well as the country that invented it. 

Kurt Vonnegut once said, “High school is closer to the core of the American experience than anything else I can think of.” If that’s so, then prom takes that experience and distills it into one night of pure-grain Americana. As tea sandwiches were replaced by tiaras and tiaras replaced by spray tans, prom has provided a yearly snapshot of American culture — our fashions, our music, our capitalism, our norms. And our prejudices: Wilcox County High School in Georgia held its first desegregated prom in 2014; some school districts still try to restrict same-sex dates. 

Yet prom has endured, becoming, every spring, an opportunity for youth culture to participate in American tradition while also, often, reacting against it: its rules, its dress code, its hetero­normativity. “It really represents the cultural imprint of the moment,” says Amy L. Best, author of Prom Night: Youth, Schools, and Popular Culture. “It’s constantly being reimagined.”

In other words, prom is an American invention that helps us continue to reinvent ourselves. And in that reinvention, prom exposes us (there’s that metaphor I was after) — as we are, and as we want to be. Inside the convention center, the country club, the cafeteria, we put ourselves on display. We smile for the camera. We hope we like what we see.

ALEX MORRIS is a senior writer at Rolling Stone covering pop culture and politics.