Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylight. Daylighting is sometimes used as the main source of light during daytime in buildings. This can save energy in place of using artificial lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants.

प्रकाश का योजनापूर्वक उपयोग करके कोई सौंदर्यपरक या व्यावहारिक प्रभाव उत्पन्न करना प्रदीप्ति कहलाती है। प्रदीप्ति के अन्तर्गत कृत्रिम प्रकाश स्रोतों एवं प्राकृतिक प्रकाश स्रोतों - दोनों का ही समुचित प्रयोग किया जाता है।