Pop's fashions have changed over the years, but the definition of a pop diva—a strong woman who unleashes showstopping songs about her high points and low moments—has stayed the same since the days of Aretha and Dusty. Soul belters like Adele and Gladys Knight set fire to any emotion; Rihanna, Cyndi Lauper and other pop supernovas flaunt their outsized personalities as they power through high-energy tracks; country stars including Dolly Parton and Carrie Underwood provide down-home charm. And uber-divas—Céline Dion, Mariah Carey—who are blessed with vocal power that can withstand any obstacle prove time and time again that they have the range.