Smog' is a term used to describe air pollution that is a combination of smoke and fog. It is caused by the emission of particulate matter into the atmosphere from the burning of fossil fuels such as coal and gasoline. Smoky fog is a type of SMOG that is created when smoke particles mix with fog, creating a thick, hazy atmosphere. This type of air pollution is often seen in cities and industrial areas where there is a high concentration of smoke-producing activities. It can cause health problems for those who are exposed to it, as the particles can be inhaled and cause respiratory issues.