A new book, "Andy Warhol: Polaroids 1958-1987," features rare images that Warhol shot of subjects, including Jack Nicholson, Audrey Hepburn and Grace Jones. Often raw and spontaneous, these Polaroids document Warhol's experiences, offering a unique record of his life and vision. Warhol once stated, "A picture means I know where I was every minute. That's why I take pictures. It's a visual diary." Pictured: Andy Warhol, c. 1972.