The nature of the hydrogen bond in addition to some other factors, such as the disordered arrangement of hydrogen in water imparts unusual properties to H2O that have made conditions favorable for life on Earth. For example, it takes a relatively large amount of heat to raise water temperature one degree. This enables the world's water bodies to store enormous amounts of heat, producing a moderating effect on the world's climate, and it makes it difficult for marine organisms to destabilize the temperature of the ocean environment even as their metabolic processes produce enormous amounts of waste heat.
One of the most important noncovalent interaction within molecules is the hydrogen bond, a dipole formed when a hydrogen atom covalently bonded to an electronegative atom is shared with a second electronegative atom (typically an oxygen, nitrogen or fluorine atom), such that the proton may be approached very closely by an unshared pair of electrons. Hydrogen bonds play a significant role in the unusual thermodynamic properties of water and ice, and the DNA double-helical and protein a-helical and b-structure conformations are extensively hydrogen bonded.
Hydrogen Bonds can be formed between different molecules (Intermolecular) or between the different parts of the same molecule(Intramolecular).