The bond which is formed between hydrogen atom and a higher electronegative atom (F, O or N) is known as Hydrogen bond. This bond involves dipole to dipole movement. The bond strength of hydrogen is very small e.g. H….F bond is 41.83 KJmol -1. Hydrogen Bond is very much weaker as compared with covalent bond.
What is Intramolecular hydrogen bonding:
The intermolecular hydrogen bond is formed between positive and negative ends of same substance but of different molecule due to electrostatic forces of attraction. On the other hand, Intramolecular hydrogen bonding is formed between the hydrogen and an electronegative element due to the electrostatic forces of attraction but present in the same molecule.
This page has really helped me a lot to understand what hydrogen bonding is.