This piece focuses light into the camera, also the distinguishing factor between an SLR and TLR camera.
What is the lens?
American photographer well-known for his black-and-white landscapes of the American West. Probably the best known photographer outside of photography circles and took (in my opinion) the greatest photo of all time (pictured below).

Who is Ansel Adams?
Allows the photographer to see what the camera is seeing
What is the view finder?
Hungarian-American photojournalist and war photographer, one of the founders of Magnum photos, and considered to be the greatest combat photographer of all time. Was killed after he stepped on a landmine.
Who is Robert Capa?
The part which allows the user to view the image through the viewfinder on a DSLR/SLR camera
What is the mirror?
American documentary photographer who is most well-known for her work during the Great Depression. Hired by the Farm Security Administration and the War Relocation Authority, most prominently. Took arguably the most famous photograph of all time.

Who is Dorothea Lange?
This allows you to mount external devices such as flashes or microphones to your camera.
What is the hotshoe?
American street photographer whose work was not discovered until after her passing. She is now retroactively considered to be one of the best street photographers of the 20th century.

Who is Vivian Maier?
This part of the camera allows the user to easily switch between different shooting modes.
What is the mode dial?
American photographer and photojournalist who documented the urban life of New York City largely in the 1930s and 40s. His best known works follow emergency situations (think crime scenes, fires, etc.). Operated under a comedic pseudonym.

Who is Weegee?