Light pollution is caused by excessive and uncontrolled artificial light from sources like outdoor advertising, projectors, and poor street lighting. It damages the atmosphere, wastes energy, and has negative impacts like progressive disappearance of visible stars, eyestrain, lack of sleep, increased risk of accidents, behavioral changes, and glare. Potential solutions include using low-energy lamps, adjusting lighting, illuminating only necessary areas, avoiding projectors, and properly directing flat, transparent lamp fixtures downward.