Why does water put out fire?

It seems a pretty simple question upon first look.The truth is, though it is a simple question, not all supply the right answer.First let me explain what water actually does to fire.

When water comes into contact with a burning object,some part of it changes into steam, for which it steals most of the heat of the burning object.After all, to transform boiling water into steam we need five times more heat than is required to heat the same amount of water from 0 to 100°C.
Secondly, the steam thus produced occupies more volume than the water giving rise to it.The steam envelops the burning object and keeps fresh air away.Without air, combustion is impossible.

Ironically though,to cause water to act as a still better extinguisher of fires, gunpowder is added to it!There is logic in this paradox.Gunpowder burns out quickly, giving off in the process a large quantity of noncombustible gas.This gas envelops the burning object and complicates combustion.