Pollution is the presence of a pollutant in the environment and is often the result of human actions. Pollution has a detrimental effect on the environment. Animals, fish and other aquatic life, plants and humans all suffer when pollution is not controlled. In other words, Pollution is the introduction of contaminants into the environment that causes harmful and toxic effects to living things. Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollution is often classified as point source pollution or non-point source pollution. Noise pollution, soil pollution and light pollution too are the damaging the environment at an alarming rate. Things as simple as light, sound and temperature can be considered pollutants when introduced artificially into an environment. Air pollution is by far the most harmful form of pollution in our environment. Air pollution is cause by the injurious smoke emitted by cars, buses, trucks, trains, and factories, namely sulphur dioxide, carbon monoxide and nitrogen oxides. Toxic pollution affects more than 200 million people worldwide. In some of the world’s worst polluted places, babies are born with birth defects, children have lost 30 to 40 IQ points, and life expectancy may be as low as 45 years because of cancers and other diseases.