The formation of compound takes place by atom in order to complete their octet and attain stability. The atom combine with other atom either by sharing of electrons or transfer of electrons from one atom to other. The sharing of electrons results in the formation of covalent bond whereas transfer of electrons results in formation of ionic bond. The loss of electron from an atom results in formation of cation whereas gain of electron results in the formation of anion. The force of attraction between the two oppositely charged ions is electrostatic force of attarction.
Hence, an ionic bond is an attraction between opposite charged ions. a covalent bond is sharing of electrons between atoms.
