What is a fossil fuel and how are they made?

Answer 1

Fossil fuels are compounds created from the decay of ancient swamps. They include peat, coal, natural gas and crude oil. A very simplified explanation of how they got made is that there was a time in paleo history when most plant material was made from lignin but there were no bacteria that could break it down, so when plants died, they just piled up on top of each other and slowly sunk into the bog. With pressure and heat they turned into the fossil fuels over millions of years. Today, most plants are made from cellulose and there are bacteria that break it down - dead plants become soil, not oil, so no new fossil fuel is being produced. Once we use up what there is in the earth, there isn't any more.