(NewsNation) — With all the talk lately about the price of oil and how Russia supplies a significant percentage of Europe’s oil and gas, let’s get our facts straight on what, exactly, we’re talking about.

The “gas” we’re talking about is natural gas, the stuff you use in your stove, to heat your house and/or to run your water heater. It can also be burned to power electric plants. It comes out of the ground ready to use, and doesn’t require any refinement.

One thing that is done to it, however, is the addition of a chemical called mercaptan, which gives it that distinct “rotten egg” smell. Natural gas by itself has no odor, so it could leak for a long time before anyone notices.

“Oil” refers to petroleum, the black liquid responsible for much of America’s industrial boom in the 20th century. Unlike gas, oil isn’t ready to use when it comes out of the ground. It has to be refined, which is a process during which the base oil is heated and different products are extracted at different temperatures to make everything from jet fuel, to premium unleaded, to roofing tar and motor oil.

Oil and gas are frequently found together, with large pockets of natural gas found adjacent to pockets of oil. In the early days, before good uses were found for natural gas, it was frequently burned off so drillers could get to the oil, for which they had a market.

The confusion comes because one of the products into which petroleum (oil) is refined is gasoline (gas), which is of course how most of us come into contact with it. Most of us know that petroleum becomes gasoline, but not as many of us know that the “gas” referred to in news stories is actually natural gas.

Oil, coal and gas are the “fossil fuels” referred to in climate change discussions. They all emit chemicals harmful to the environment when burned, although coal and oil are “dirtier” than natural gas.