Conventional Lighting instruments:
Stage lighting instruments are used to illuminate theatrical productions, rock concerts and other events taking place in live performance venues. They are also used to light television studios and sound stages.
Terminology is different between the USA and UK for many stagecraft terms. In the USA, lighting fixtures are called "instruments." In the UK, they are called "lanterns" or "luminaires".
What they all have in common is that they are housings for lamps and rely on a dimming system to supply the power and control of brightness or intensity. Fixtures with more than intensity control are call intelligent fixtures and can be found >here<.
Architectural lighting instruments are electrical devices used to create artificial light or illumination in architecture. A complete lighting fixture unit consists of the light source or lamp, the reflector for directing the light, an aperture (with or without a lens), the outer shell or housing for lamp alignment and protection, an electrical ballast, if required, and connection to a power source.