Considerable importance in stabilizing structures by intramolecular bond formation
Not as important in intermolecular bonding in aqueous solutions. Why?
Based on electrostatic interaction between the nonbonding electron pair of a heteroatom (e.g. O, N, and S) as the donor, and the electron deficient hydrogen atom that is chemically bonded to a more electronegative atom (e.g. SH, NH, and OH).