What is the difference between the Oscar for Cinematography and Art Direction?

The cinematography is "overall" way a film looks when you view it. Art Direction is the way the shots are set up to appear on film, set dressings, actor/character placement and costumes appearing on film. The art director is interested in the use of colors, textures and such. Whereas the cinematographer is interested in lighting for film and the use of shadow and texture to convey the "message" of the film.