In photography and cinematography, available light (also called ambient light or practical light) refers to any source of light that is not explicitly supplied by the photographer for the purpose of taking pictures. The term usually refers to light sources in the surrounding environment that are present naturally (such as sunlight or moonlight) or artificial lighting that is already pre-existing (such as street lights or room lights). It generally excludes flashes, although arguably flash lighting provided by other photographers shooting simultaneously in the same space could be considered available light. Light sources that affect the scene and are included in the actual frame are called practical light sources, or simply practicals.
Available light is an important factor in candid photography in order not to disturb the subjects.