Any fan of classic pop music of the ‘80s, ‘90s and ‘00s is a fan of Diane Warren—but they might not know it. Perhaps one of the most gifted and prolific songwriters of all time, Warren has been behind some of the career-defining hits of acts like Aerosmith, Beyoncé, Toni Braxton, Justin Bieber, DeBarge, Kelly Clarkson, Celine Dion and many more.