The element with the atomic symbol for sodium is Na. Sodium is an alkali metal that is highly reactive and is found in group 1 of the periodic table. Its name derives from the Latin word "natron," which refers to a naturally occurring mineral form of sodium carbonate. Sodium is essential for various biological functions, including fluid balance and nerve transmission in living organisms. It is commonly found in nature, primarily in the form of sodium chloride, or table salt, which is widely used in cooking and food preservation.