­ Q: Why can't we manufacture water? A: To create water, two hydrogen molecules must hook up to an oxygen molecule. Mixing them together doesn't help; you're still left with just separate hydrogen and oxygen molecules. The orbits of each molecule's electrons must link together, and to do that we must have a sudden burst of energy -- like a spark -- to get these shy things to hook up. That spark, depending on the size of the experiment, could prove deadly in a massive explosion.

Water is becoming an increasingly important issue in the developed world. But this issue is nothing new for other, less developed nations. For centuries, clean drinking water has been hard to come by for many populations, especially the poor. In some areas, water may be availabl­e, but it's often disease-ridden, and drinking it can be fatal. In other areas, a viable water supply is simply not available at all.

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A 2006 United Nations report estimated that as much as 20 percent of the world's population doesn't have access to clean drinking water [source: BBC]. This leads us to wonder: If we need it so badly, why can't we just make it?

Water is made of two hydrogen molecules attached to an oxygen molecule. This seems like pretty basic chemistry, so why don't we just smash them together and solve the world's water ills? Theoretically, this is possible, but it would be an extremely dangerous process, too.

To create water, oxygen and hydrogen molecules must be present. Mixing them together doesn't help; you're still left with just separate hydrogen and oxygen molecules. The orbits of each molecule's electrons must become linked, and to do that we must have a sudden burst of energy to get these shy things to hook up.

David McNew/Getty Images Living with a waning drinking supply has long been a fact of life for many countries. In the Western world, it's a new, yet serious problem.

­Since hydrogen and oxygen are both extremely flammable, it wouldn't take much to create this force. Pretty much all we need is a spark -- not even a flame -- and boom! We've got water. The hydrogen and oxygen molecules' electrons' orbits have been conjoined.

But we also have an explosion and -- if our experiment was big enough, a deadly one. The ill-fated blimp, the Hindenburg, was filled with hydrogen to keep it afloat. As it approached New Jersey on May 6, 1937, to land after a trans-Atlantic voyage, static electricity (or an act of sabotage, according to some) caused the hydrogen to spark. When mixed with the ambient oxygen in the air, the hydrogen exploded, enveloping the Hindenburg in a ball of fire that completely destroyed the ship within half a minute.

There was, however, also a lot of water created by this explosion.

To create enough drinking water to sustain the global population, a very dangerous and incredibly large-scale process would be required. Still, over a century ago the thought of an internal combustion engine -- with its controlled repeated explosions -- seemed dangerously mad. And as water becomes scarcer, the process of joining hydrogen molecules to oxygen molecules may become more attractive than it is currently. Necessity, after all, is the mother of invention.

Video Gallery: Saving Water There are more than 300 million trillion gallons of water on Earth -- if we divided it evenly, each person would have 40 billion gallons to themselves. To learn more about water and its amazing properties, check out this HowStuffWorks video. Learn how a few simple changes, such as installing a low-flow shower head, can reduce your water waste. Brought to you by the Discovery Channel.

But there are safer ways of creating water out of thin air, and projects to do just that are already underway. Read the next page to learn about a few mad scientists who may end up solving the world's impending water crisis.