Asymbol is a data type that represents unique, unforgeable identifiers. They are sometimes calledatoms.

Because a symbol is unique and unforgeable, you can only read a property value associated with a symbol if you have a reference to the original identifier.

In JavaScript,symbol is one of theprimitive types and can be created using theSymbol() factory method that returns a different symbol each time. They can be used as keys for objects which can never accidentally collide with other properties.

JavaScript also defines two other categories of symbols: well-known symbols and registered symbols. Read theSymbol reference for more information.

See also

• Data types on Wikipedia
• Symbol on Wikipedia
• The JavaScript global objectSymbol