Camera : An electronic device for recording images and videos. Lens A piece of transparent material (as glass) that has two opposite regular surfaces either both curved or one curved and the other plane and that is used either singly or combined in an optical instrument for forming an image by focusing rays of light. b : a combination of two or more simple lenses. Aperture definition A device that controls the amount of light that is allowed through an opening. Exposure definition : How long light is exposed to the image or light sensitive paper. Shutter definition : a device in a camera that opens to let in light when a picture is taken Focus definition : The sharpness of an image i.e blurry has low focus ISO Is the level of sensitivity of your camera to available light. Enlarger an optical instrument for making enlarged photographic prints in which a negative is brightly illuminated and its enlarged image is focused onto a sheet of light sensitive paper. F-number the size of the entrance to the camera Iris controls the amount of light coming through the lens .