In chemistry, a salt is a chemical compound composed of cations (positively charged ions) bound to anions (negatively charged ions). They are typically the product of a chemical reaction between a base and an acid, the base contributing the cation and the acid contributing the anion.
One example is table salt, in common usage often simply called salt. It is the specific salt sodium chloride, and is described thoroughly in that article. Its formula is NaCl and it is the product of the base sodium hydroxide, NaOH and hydrochloric acid, HCl. Table salt is the same as sea salt.
In general, salts are ionic compounds which form crystals. They are usually soluble in water, where the two ions separate. Salts typically have a high melting point, low hardness, and low compressibility. If molten or dissolved in water, they conduct electricity.