The property of polar water molecules is to build hydrogen bonds.
The hydrogen bond (H-bond) is a type of weak chemical bond based on electrostatic attraction between hydrogen atoms and a nucleophilic atom containing free electronic pairs. This bond is possible when hydrogen is associated with a covalent bond with a high electronegativity atom (e.g., oxygen, fluorine, nitrogen), wherein the partial charge is highly delocalized at the ends of small, compact molecules of this type.