Question

what is ionic bonding?

Answer 1

ionic bonding is that chemical bonding which is formed by the transfer of electrons from one atom to another.
An ionic bond is formed when one of the atom donate electrons to other to  achieve inert gas configuration and the other atom needs electrons to achive its inert gas configuration.
Metals and non-metals combine to form ionic bond.

Answer 2

this bond is formed due to transfer of electrons from one atom to another