Before Ozzy Osbourne and Black Sabbath, metal was just a building material. One of six children born to a family of factory workers in postwar Birmingham, England, Osbourne would come to define the persona of the heavy-metal frontman, blurring the line between dramatic flair and what at times seemed like genuine madness. Bleak, primitive, and relentlessly loud, his music—both with Black Sabbath and in his solo career—provided stark counterpoints to the airy excesses of '60s and '70s rock, marked by haymakers like “Paranoid,” “Crazy Train,” “Sweet Leaf,” and “Supernaut.” And though he's known for his screeching, almost acidic voice, Osbourne was surprisingly handy with ballads too—just revisit Sabbath’s disarming “Changes” or 1991’s “Mama I’m Coming Home.” A natural provocateur, Osbourne went on to play avatar for parents’ nightmares worldwide; he was singled out during both the satanic panic of the mid-’80s and the 1985 Senate hearing that led to the RIAA’s adoption of the now-infamous “parental advisory” stickers. His star continued to grow throughout the ’90s, first as the namesake of the hugely successful Ozzfest (hatched by his wife and manager, Sharon), then—and maybe most implausibly—as the affable, befuddled dad of reality TV’s The Osbournes. Still, Osbourne retains the image of a survivor—the poor-boy-made-good—and his sense of humor has ripened over time. “I’m a lunatic by nature, and lunatics don’t need training,” he wrote in his autobiography, I Am Ozzy. “They just are.”