Single-lens Reflex

Aperture - (noun) an opening, as a hole, slit, crack, gap, etc.
Shutter - (noun) a mechanical device for opening and closing the aperture of a camera lens to expose film or the like
Exposure - (noun) an act or instance of revealing or unmasking, as an impostor, crime, or fraud
Depth of Field - (noun) the range of distances along the axis of an optical instrument, usually a camera lens, through which an object will produce a relatively distinct image
F-Stop - (noun) the setting of an adjustable lens aperture, as indicated by an f number
Focal Length - (noun) the distance from a focal point of a lens or mirror to the corresponding principal plane

Import Words:
Parallax - (noun) the apparent displacement of an observed object due to a change in the position of the observer
Pentaprism - (noun) a prism that has five faces, a pair of which are at 90 degrees to each other; a ray entering once of the pair emerges from the other at an angel of 90 degrees to its original direction: used especially in single-lens reflex cameras to reverse images laterally and reflect them to the viewfinder
Pellicle - (noun) a thin, partially reflective coating, as on a beam splitter or pellicle mirror
Optical - (adjective) of or pertaining to sight or vision; visual

The Canon Rebel T3 buttons consists of viewfinder diopter adjustment, aperture/exposure compensation/erase button, live view/movie record, AE lock, AF point selection, quick control, ISO, drive mode, white balance, AF mode, playback, display button, mode dial, shutter button, main dial,flash button, auto/manual focus switch, image stabilizer switch, and lens release button.