Salt water, or saline water, contains a variety of dissolved compounds. The most abundant compound in salt water is sodium chloride (NaCl), which is common table salt. Other compounds found in salt water include magnesium chloride (MgCl2), calcium sulfate (CaSO4), and potassium chloride (KCl). The exact composition of salt water can vary depending on the source of the water, such as the ocean, a lake, or a river.