* Ionic Compounds: Formed by the electrostatic attraction between oppositely charged ions (cations and anions).

* Sodium (Na) readily loses an electron to become a positively charged ion (Na+).

* Chlorine (Cl) readily gains an electron to become a negatively charged ion (Cl-).

* Molecules: Formed by the sharing of electrons between atoms through covalent bonds.

In NaCl:

* Sodium (Na) loses an electron, forming a positive ion (Na+).

* Chlorine (Cl) gains an electron, forming a negative ion (Cl-).

* The strong electrostatic attraction between the positively charged sodium ions and negatively charged chloride ions forms the ionic compound, sodium chloride.

Key Differences:

* Bonding: Ionic compounds have ionic bonds, while molecules have covalent bonds.

* Structure: Ionic compounds form crystal lattices, while molecules can exist as individual units.

* Melting/Boiling Points: Ionic compounds generally have higher melting and boiling points than molecular compounds due to the strong electrostatic forces between the ions.

Therefore, NaCl is an ionic compound due to the presence of ionic bonds and the formation of a crystal lattice.