Covalent bonds form by sharing of electrons and ionic bonds are formed by donating electrons.
Step-by-step explanation:
Covalent bonds are formed between less electronegative and less electropositive atoms of elements. These atoms are unable to donate the electrons or accept them fully because of their affinity towards these electrons.
Ionic bonds are formed between the more electronegative and electropositive atoms of elements. They fully donate or accept the electrons to fulfill their octet. Thus, they are only attracted towards each other by means of electrostatic force of attraction. There’s no actual bonds present between the atoms unlike those in the covalent atoms.