* Compound: A substance formed when two or more different elements are chemically bonded together in a fixed ratio.

* Mixture: A combination of two or more substances where each substance retains its own properties.

In the case of NaCl (Sodium Chloride), which is table salt:

* Sodium (Na) and Chlorine (Cl) are chemically bonded together in a 1:1 ratio.

* The resulting compound, NaCl, has entirely different properties than either sodium or chlorine individually. Sodium is a highly reactive metal, and chlorine is a poisonous gas. When combined, they form a stable, edible compound.

Therefore, NaCl is a compound, not a mixture.