| A | B |
|---|
| Nonrenewable resource | A natural resource that is being used up faster than it can be replaced by natural processes |
| Renewable resource | A natural resource that can be replenished by natural processes at least as quickly as it is used |
| Fossil fuel | A nonrenewable resource formed over millions of years from the remains of prehistoric organisms; for example: coal, oil and natural gas |
| Coal | A solid fossil fuel formed from decayed plant material |
| Oil | A liquid fossil fuel formed from decayed marine organisms |
| Natural gas | A gaseous fossil fuel formed from marine organisms that is often found above a layer of oil |
| Nuclear energy | Energy stored in and released from the nucleus of an atom |
| Solar energy | Energy produced using rays from the sun |
| Wind energy | Energy produced by the rotation of blades on a large generator due to changes in air temperature |
| Hydroelectric energy | Energy produced by flowing water |
| Geothermal energy | Energy produced from hot magma or hot, dry rocks from below Earth’s surface |
| Biomass energy | Energy produced by burning organic matter, such as wood, food scraps, and alcohol |
