Water is considered the greatest solvent in the world because it dissolves more substances than any other solvent. Water is considered a universal solvent.
As water penetrates different surfaces, such as the ground and the human body, it takes along with it vitamins and nutrients that are vital to life. It is also used to grow vegetation which is important for life.
Water contains a negative and positive charge which makes it ideal for attracting other types of molecules. It becomes attracted to some molecules more than others. When mixed with salt, for instance, the salt dissolves as the water disrupts the molecules.