The only bond that involves the complete transfer of electrons is ionic bonding.
A metal that does not have much care for its electrons, such as Sodium, Na, is willing to give up its electron more freely. And an atom that really cares about having electrons might be a gas such as chlorine, Cl. The Chlorine atom takes the electron from Sodium, and then the newly formed ions of Na+ and Cl- bond because they have equal and opposite charges and opposites attract. NaCl is formed.
Hydrogen bonds aren’t actually real bonds (I know, the name is deceptive)
Covalent bonds involve the sharing of electrons.
I’m pretty sure metallic bonds is a made-up term.
