This has a partial positive charge, this has a partial positive charge and this nitrogen will have a partial negative charge. So we have a partial positive charge here and right next to it on the other molecule we have a partial negative charge on the nitrogen. And so we have the existence of these two partial charges that are opposite in nature and that will be an attractive force. 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.