The biggest part of water on earth is salty water, in the oceans and seas. They occupy the biggest part of our planet.
The water molecule, H2O, is a tiny, light and rather polar molecule, and it is an important dipole.
The fact of being a dipole molecules corresponds with the fact that the two H atoms make an angle to the O atom.
Both OH-bonds are polar covalent bonds with a large difference in Electronegativity (ΔE).
This dipole character is responsible for the important characteristics of water, like boiling point and melting point.
Sea water contains about 35 milligram solid per liter: