Fossil fuels are carbon based fuels.
They were created millions of years ago from decaying plant materials.
They include oil, coal and gas.
When burned, fossil fuels release carbon dioxide and carbon monoxide.
85% of the world electrical energy comes from fossil fuels.
The fuel is burned, and the heat turns water to steam, which turns turbines making electrical energy.
While cheap and easy to use, fossil fuels have many disadvantages:
A duck covered in oil from a spill in San Francisco bay