Driving a car is the most air polluting act the average citizen commits. Air pollution is defined as a gaseous, liquid, or solid substance that interferes with human comfort, health or welfare, and causes environmental damage. Air pollution plays as a key component to green house gases. Green house gases allow sunlight to enter the atmosphere freely. When the sunlight hits the Earth’s surface, some of the sunlight is re-radiated back towards space. The greenhouse gases absorb the infrared radiation and trap its heat in the atmosphere. By trapping this heat in the atmosphere, the Earth has encountered drastic climate and environmental changes which is known as global warming. Because of global warming, the sea level has risen due to the melting of glaciers. In addition, forests have been drying out because of the extremely high temperatures. These environmental changes have occurred mainly because of air pollution. Air pollution that is produced in urban areas is mostly caused by motor vehicles. Motor vehicles produce large amounts of nitrogen oxides, hydrocarbons, and carbon monoxides. When the motor vehicle reaches high pressure and temperatures, oxygen and nitrogen atoms react to one another and produce nitrogen oxides. In a car’s exhaust system, the catalytic converter breaks down the heavier nitrogen gases and creates nitrous oxide. Nitrous oxide, making up about seven percent of the gases that cause global warming, is extremely potent as a green house gas. Nitrous oxide reacts with hydrocarbons and sunlight to form ground-level ozone. Ground-level ozone is a key component of smog. Ground-level ozone irritates the nose, eyes, throat and damages the lungs. Numerous exhaust hydrocarbons are toxic and some can cause potential cancer. Carbon monoxide is another dangerous gas that is produced when fossil fuels burn incompletely due to a lack of oxygen. Carbon monoxide can be formed in a car when the air to fuel ratio is too low when starting a car. This gas can also be produced if a car is not tuned properly or if the car is in high altitudes. Carbon monoxide is a poisonous gas that does not have an odder or a color. Two thirds of the carbon monoxide comes from transportation. The largest of contributor of these transportation sources are cars. Car exhaust also produces a colorless gas called sulfur dioxide. High exposures to sulfur dioxide can result in burning of the nose and throat, having breathing difficulties, and can be life threatening. The burning of hydrocarbons releases carbon dioxide into the atmosphere. Carbon Dioxide gas is one of the most major pollutants in our atmosphere. Carbon dioxide is good at transmitting light and preventing infrared radiation from going back into space. Because of these qualities, carbon dioxide is a green house gas. Carbon dioxide is responsible for fifty seven percent of global warming. Because driving a car is the most air polluting action that the average citizen commits, it is imperative to limit the use of cars by car-pulling and to spread the awareness of air pollution to achieve the ultimate goal of keeping a safe and healthy environment