Hilary Erhard Duff is an American actress, singer-songwriter, entrepreneur, and book author. After working in local theater plays and television commercials in her childhood, Duff gained fame playing the title role in the Disney Channel television series Lizzie McGuire. She subsequently has appeared in films, including The Lizzie McGuire Movie, Cheaper by the Dozen, A Cinderella Story and Cheaper by the Dozen 2.
As a singer, Duff released an RIAA-certified triple-platinum debut album, Metamorphosis. Her next two albums, Hilary Duff and Most Wanted, were certified platinum. Her 2007 album Dignity was certified gold and spawned her highest charting US single as of 2011, "With Love". Best of Hilary Duff, a greatest-hits compilation, was released in late 2008. Duff has sold over 13 million records worldwide. Billboard ranked her the 69th best selling artist of the 2000s.
Duff has also launched her own clothing lines, Stuff by Hilary Duff and Femme for DKNY Jeans, and signed with IMG Models. She has also released two perfume collections with Elizabeth Arden. Her other business ventures include writing a young adult novel, Elixir, and working as an executive producer for the film According to Greta and as a producer for the films Material Girls and Beauty & the Briefcase.