Here's why it's not a true bond:

* True bonds involve the sharing or transfer of electrons: Covalent bonds involve the sharing of electrons between atoms, while ionic bonds involve the transfer of electrons from one atom to another.

* Hydrogen bonds are weaker: They arise from the electrostatic attraction between a partially positive hydrogen atom and a partially negative atom (usually oxygen or nitrogen), and they are weaker than true covalent or ionic bonds.

So, hydrogen bonds are not true bonds, but they are important for many biological processes. They help to hold DNA strands together, stabilize protein structure, and allow water molecules to form strong interactions.