Salt is a compound, not an element. Table salt, for example, is sodium chloride, a chemical compound with the formula NaCl. It is made from two elements: sodium, or Na, and chlorine, or Cl.
Chemical compounds are chemical substances that are made of two or more different chemical elements. In the case of table salt, it is a compound because it is made from two different elements. Salts are ionic compounds that occur when an acid is neutralized by reacting with a base. Other types of salts besides common table salt are sodium bicarbonate, or NaHCO3, sodium hydrosulfide, or NaHS, sodium bisulfate,or NaHSO4, monosodium phosphate, or NaH2PO4, and disodium phosphate, or Na2HPO4.