Air pollutants are harmful substances in the air that can affect human health and the environment. Common types include particulate matter, nitrogen oxides, sulfur dioxide, and volatile organic compounds. These pollutants can come from various sources, such as vehicle emissions, industrial processes, and natural events like wildfires. Exposure to air pollutants can lead to respiratory issues, cardiovascular diseases, and other health problems. Additionally, they can contribute to environmental issues like acid rain and climate change. Monitoring and reducing air pollution is essential for improving air quality and protecting public health.