Ansel Adams is one of the greatest photographers the U.S.A. has ever had. He is best known for the black and white photographs of the Yosemite National Park. Adams was also one of the pioneers of documentary photography and the creator of a photographic technique called Zone System. This is a technique used for determining the correct film exposure and development.
Adams, along with Imogen Cunningham and Edward Weston, have founded the Group f/64, a starting point for the later established department of photographic art, part of the Museum of Modern Art.