Lighting is the arrangement and use of light sources to illuminate a space or object. When you turn on lamps in your room, adjust your desk light for homework, or notice how stage lights make performers visible in a dark theater, you're experiencing lighting at work.

Good lighting matters more than most people realize. In a classroom, poor lighting can make it hard to read or cause headaches. In a museum, careful lighting protects fragile paintings while still letting visitors see them clearly. Theater and film crews spend hours setting up lighting to create specific moods: bright, cheerful lighting for a comedy scene versus dim, shadowy lighting for something mysterious or scary.

The word can also refer to the lights themselves as a group. An architect might design the lighting for a new library, choosing where fixtures go and how bright they should be. A photographer adjusts their lighting to make their subject look just right.

Natural lighting comes from the sun, while artificial lighting comes from bulbs, LEDs, candles, or other human-made sources. Interior designers think carefully about lighting because the same room can feel cozy and warm or cold and uninviting depending on how it's lit.