A chemical symbol is an abbreviation or short representation of the name of a chemical element. Natural elements all have symbols of one or two letters; some man-made elements have symbols of three letters.
Chemical symbols are listed in the periodic table and are used as shorthand and in chemical equations, e.g., 2 H2 + O2 → 2 H2O
Because chemical symbols are often derived from the Latin or Greek name of the element, they may not bear much resemblance to the common English name, e.g., Na for sodium (Latin natrium) and Au for gold (Latin aurum).
For complete listings of the chemical elements and their symbols, see: