Since the population is growing, pollution is also growing right along with it. The discharges of the greenhouse gases have increased more than what they were expected to do. So in return, people should plant more trees to absorb the carbon dioxide that is being produced. In first world countries it is used as a substitute for coal, because petroleum and natural gas are much more clean and environmentally safe. They also contribute less to habitat destruction and air pollution.
Petroleum is a fossil fuel.
It was formed many millions of years ago. Some say that it formed before the dinosaurs were even here. The process involves the extraction of crude oil from the earth and is formed by liquidation. It is formed when the pressure between small cracks in the rocks builds up and shoots out, hopefully going into a pipeline , meaning the direction of the well, if planned flawlessly. This may happen naturally or man may have to provide the pressure with machines.