Pollution is the introduction of contaminants into the natural environment that cause adverse changes. The presentation discusses different types of pollution including air, water, land, noise, and dust pollution. Air pollution involves a combination of natural gases with dangerous gases. Water pollution occurs when pollutants reach bodies of water without treatment. Land pollution results from excess dumping of toxic waste. Noise pollution disturbs the silent environment with loud noise. Dust pollution contaminates the air with particles. The document briefly states that pollution can be harmful to health due to smoking and drinking alcohol.