| Term | Definition |
| fossil fuels | made from living matter millions of years old |
| renewable energy | anything capable of producing energy and can be used over and over again. ex sunlight and wind power. |
| non renewable energy | when you use up this kind of energy, it's gone for good |
| fractional distillation | heating petroleum separate the parts, like gasoline and asphalt |
| efficiency | the percentage of energy that is actually used to perform work |
| nuclear energy | energy obtained from nuclear reactions |
| fission | the splitting of uranium atoms |
| thermal | relating to or associated with heat |