Answer :
Atoms share pairs of electrons : Covalent
Atoms transfer electrons : Ionic
Atoms have electrostatic attraction : Ionic
Atoms bond together : Both
Explanation :
Covalent compound : The compounds where the atoms are covalently bonded.
Covalent bonds are formed by the equal sharing of electrons. These bonds are commonly formed between two non-metals.
Ionic compound : The compounds where the atoms are bonded through ionic bond and atoms are bonded by the electrotstatic attraction.
Ionic bonds are formed by the complete transfer of electrons. The atom which looses the electron is considered as an electropositive atom and the atom which gains the electron is considered as electronegative atom. These bonds are formed between one metal and one non-metal.