The document discusses various types of pollution including air pollution. It defines pollution as the introduction of substances that cause adverse environmental changes. Air pollution is caused by the release of pollutants such as gases, particles, and biological molecules into the air from sources like vehicle emissions, industrial effluence, and more. Some key effects of air pollution include respiratory diseases, global warming, acid rain, and ozone layer depletion. Prevention methods include afforestation, limiting industrial emissions, and reducing automobile use. The document also discusses some major air pollution disasters such as the Bhopal gas tragedy and the Great Smog of London.