This document summarizes four main types of pollution: air, water, noise, and land pollution. It defines each type and discusses their causes and effects. For air pollution, it notes major sources are industries and automobiles, and effects include impacts on human health, animals, plants, and the atmosphere. For water pollution, it states 40% of deaths are caused by contaminated water from industrial and sewage waste. Noise pollution stems from traffic, construction, industries, and has health impacts like hearing loss and stress. Land pollution results from mining, household garbage, and industrial waste contaminating the earth. The document provides suggestions for preventing each type of pollution.