Avril Lavigne’s sharp, punk-informed pop can mean everything to any girl who’s ever felt like an outsider. Born in Ontario, Canada, in 1984, the singer/songwriter was initially positioned as a teen antihero—a rowdy, refreshing, slightly tomboyish counter to the coy, curated, overtly sexual stylings of chart dominators like Britney Spears and Christina Aguilera. And with the release of her 2002 debut album, Let Go, Lavigne didn’t just go against that glossy image, she shattered it, spiking her hooks with sass and sincerity and making loose neckties and a tank top a must-have fashion statement. The young spitfire faced love with intimidating confidence—she not only fell for the “Sk8er Boi,” she wrote songs with him—and approached poseurs with eye-rolling distaste, as expressed on her breakout single “Complicated.” Moving on from her teens, Lavigne’s kept that youthful spirit and outspoken edge alive, empowering girls to stand up for themselves (2004’s post-grunge earworm “Don’t Tell Me”), maybe steal a boy or two in the process (2007’s bubbly pop-punk anthem “Girlfriend”), and never, ever lose touch with their wild side (2013’s punky sing-along “Here’s to Never Growing Up”). She’s continually reinvented herself, too, moving effortlessly between romantic balladeer, stadium-rock warrior, and a “bombshell raisin’ hell”—while baring all, even through public breakups and an enduring battle with Lyme disease. It’s been enough to keep Lavigne in the spotlight, both on her own and as a major influence on notable admirers like Billie Eilish.