So what is the big deal about water anyway? Let's start by saying that WATER IS AMAZING! Water is the only substance on Earth that is found in all three physical forms -- liquid, solid (ice & snow), and gas (water vapor). Water can cut through stone, dissolve more substances than any other liquid on Earth, and is key to life. We have a finite amount of water on this planet but it's always moving through the water cycle. It's so cool! And SO important to life on Earth.

Believe it or not, the secret to water's importance is in its chemistry. You don't have to be a chemist to get a sense of what makes water pretty special, but it helps to understand the basics.

Chemistry of Water

At it's most basic, a single water molecule is made up of three atoms: two hydrogen (H) atoms and one oxygen (O) atom -- H2O. A single drop of water contains billions of tiny water molecules. The structure of a water molecule gives it a charge, or what is called polarity. The polarity of a water molecule makes it sticky, so it wants to stick to other similar water molecules (adhesion) and stick to other substances like a leaf or your skin (cohesion).

The polarity of a water molecule also means that other types of molecules are attracted to it and even break apart when they stick. This is what makes water one of the most effective solvents on Earth. Water is considered the "universal solvent" meaning it can dissolve or break down molecules of more substances than any other liquid on Earth. It means that wherever water goes -- through the air, the ground, or through our bodies -- it takes chemicals, minerals, and nutrients with it.

So How Does water move?