Pollution is the introduction of contaminants into the natural environment that cause adverse changes. It can take the form of chemical substances or various types of energy pollution including noise, heat, and light pollution. The main types of pollution discussed are air, land, noise, and water pollution. Air pollution harms humans, crops, and the environment. Land pollution results from improper waste disposal and chemicals from agriculture. Noise pollution is disturbing or excessive noise that harms humans and animals. Water pollution contaminates water bodies and affects entire ecosystems. The effects of pollution include various health problems and environmental damage. Remedial measures include proper waste disposal, emissions controls, water treatment, and reducing pollution at the source.