Sodium is salt
It is a soft, silver-white, highly reactive metal. In the Periodic table it is in column 1 (alkali metals), and shares with the other six elements in that column that it has a single electron in its outer shell, which it readily donates, creating a positively charged atom — a cation.
This guy was the dude who found out about sodium best remembered today for his discoveries of alkaline metals as well as contributions to the discoveries of the elemental nature of chlorine.
The most common compound of sodium is sodium chloride (common salt). It is added to food and used to de-ice roads in winter. It is also used as a feedstock for the chemical industry. Sodium carbonate (washing soda) is also used to deodorize refrigerators, some people use it to brush their teeth but you have to mix it with some lemon and it tastes bad but it works.