Shamelessly borrowed from Wikipedia:
Ansel Easton Adams (February 20, 1902 – April 22, 1984) was an American photographer and conservationist. His black-and-white landscape photographs of the American West, especially Yosemite National Park, have been widely reproduced on calendars, posters, and in books.
“Once destroyed, nature’s beauty cannot be repurchased at any price.” – Ansel Adams
With Fred Archer, Adams developed the Zone System as a way to determine proper exposure and adjust the contrast of the final print. The resulting clarity and depth characterized his photographs. Adams primarily used large-format cameras because their high resolution helped ensure sharpness in his images.
You can read more about Adams HERE.