Smog is a combination of smoke and fog that can harm humans, animals, and plants, leading to over 2.4 million deaths per year from air pollution and increased risks of lung cancer and heart disease. The document provides suggestions for reducing smog such as carpooling, using solar energy instead of fossil fuels, unplugging appliances, biking instead of driving, and using less gasoline and electricity to help improve air quality and the health of both people and the environment.