SLR - A single-lens reflex (SLR) camera. This is a camera that typically uses a semi-automatic moving mirror system that permits the photographer to see exactly what will be captured by the film or digital imaging system (after a very small delay).
Lens - a transparent optical device used to converge or diverge transmitted light and to form images
Shutter - a mechanical device on a camera that opens and closes to control the time of a photographic exposure
Shutter speed control - common term used to discuss exposure time, the effective length of time a camera's shutter is open.
Aperture – a device that controls amount of light admitted
ASA/ISO - Speed rating for photographic materials devised by the American Standards Association.
Shutter Button - a button found on many cameras, used to take a picture. When pressed, the shutter of the camera is "released", so that it opens to capture a picture, and then closes, allowing an exposure time as determined by the shutter speed setting
Rewind Knob - this is usually rest around pentaprism of the camera. It has an electrical contact which mated with a contact in the mounting foot of the flash unit.
