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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Symbol - Glossary | MDN | 1/3 | https://developer.mozilla.org/en-US/docs/Glossary/Symbol | reference | web, html, css, javascript, documentation | 2026-05-05T05:46:23.165268+00:00 | kb-cron |
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Symbol
A symbol is a data type that represents unique, unforgeable identifiers. They are sometimes called atoms.
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 the primitive types and can be created using the Symbol() 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 the Symbol reference for more information.
In this article
See also
- Data types on Wikipedia
- Symbol on Wikipedia
- The JavaScript global object
Symbol