Fire can destroy your house and all of your possessions in less than an hour, and it can reduce an entire forest to a pile of ash and charred wood. It's also a terrifying weapon, with nearly unlimited destructive power. Fire kills more people every year than any other force of nature.


But at the same time, fire is extraordinarily helpful. It gave humans the first form of portable light and heat. It also gave us the ability to cook food, forge metal tools, form pottery, harden bricks and drive power plants. There are few things that have done as much harm to humanity as fire, and few things that have done as much good. It is certainly one of the most important forces in human history. But what is it, exactly?

In this edition of HowStuffWorks, we'll find out where fire comes from and see why it behaves the way it does. The answers might surprise you!