The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites.

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In the United States and the rest of the industrialized world, gasoline is definitely a vital fluid. It is as vital to the economy as blood is to a person. Without gasoline (and diesel fuel), the world as we know it would grind to a halt. The U.S. alone consumes something like 130 billion gallons (almost 500 billion liters) of gasoline per year!

What is it in gasoline that makes it so important? In this article, you will learn exactly what gasoline is and where it comes from.