Interior lighting refers to the artificial illumination of indoor spaces such as homes, offices, and other buildings. Its primary function is to provide adequate light for visibility and to support various activities, regardless of the availability of natural light. In addition to its practical role, interior lighting contributes to creating a desired atmosphere, enhancing the visual appeal of a space, and promoting comfort and security.

A variety of sources can be used for indoor lighting, including incandescent bulbs, fluorescent lamps, LED lights, and natural elements like windows and skylights. Lighting can be customised in terms of brightness and colour temperature to meet different needs and preferences. Effective lighting design considers the purpose of the space, the activities conducted there, and the individual preferences of its occupants.

There are several types of indoor lighting fixtures, such as ceiling lights, floor lamps, table lamps, wall sconces, and track lighting. Each serves a specific function and can be used to create different effects, including ambient lighting, task lighting, or accent lighting.

Since indoor lighting can contribute significantly to a building's overall energy use, selecting energy-efficient lighting options and designing layouts that maximise natural light can help reduce energy consumption and lower carbon emissions.