And this bond is known as the hydrogen bond because this hydrogen atom is being shared by these two electronegative atoms. Likewise, because we have a partial positive charge on this H atom it is being shared by these two electronegative atoms namely the nitrogen and our oxygen. So that is what a hydrogen bond is. A hydrogen bond exists between two different groups of atoms that have a permanent dipole moment. So what that means is there's a permanent dipole moment right here and there's also permanent dipole moment right over, let's say right over here. And so these two permanent dipole moments interact with one another and they form a bond.