Aperture- an opening, hole, or gap.
Shutter- a device that opens and closes to expose the film in a camera.
Exposure.
Depth of field- The distance between the nearest and the furthest objects that give an image judged to be in focus in a camera.
F-stop- a camera setting corresponding to a particular f-number.
Focal length- he distance between the center of a lens or curved mirror and its focus.