This document summarizes four main types of pollution: soil pollution, water pollution, air pollution, and sound pollution. Soil pollution is caused by human-made chemicals or alterations that contaminate the natural soil environment. Water pollution results from contamination of water bodies, often from human activities like detergents and waste. Air pollution occurs when harmful substances like gases, particulates, and biological molecules from sources such as fossil fuel burning and industries are introduced into the atmosphere. Sound pollution, also called environmental noise, is noise that harms human or animal activity caused by sources including transportation, construction, and social events.