What are the five sources of lights that are not hot?

Five sources of light that are not hot include LED lights, fluorescent lights, cold cathode lights, fiber optic lights, and certain types of phosphorescent materials. These sources emit light through various processes that do not involve significant heat generation, making them energy-efficient and safer to touch. For example, LEDs use a semiconductor to produce light, while fluorescent lights excite gas to emit light without generating much heat.