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## Resource: About Function Libraries

## Article: About Function Libraries

## Article Link: https://dev.wix.com/docs/site-extensions/function-libraries/about-function-libraries.md

## Article Content:

# About Function Libraries

A [function library](https://dev.wix.com/docs/overview/extensions-framework/site-extensions/function-libraries.md) bundles reusable, stateless functions that components can use through editor binding. This reference documents the files that define a function library and the manifest fields that connect its implementation to the editor and runtime.

Function libraries are currently only available for Studio Two sites.

## What's in this reference

This reference includes the following articles:

- [Function Library Extension Files and Code](https://dev.wix.com/docs/site-extensions/function-libraries/function-library-extension-files-and-code.md): The manifest and implementation files and how they correspond.
- [About the Function Library Manifest](https://dev.wix.com/docs/site-extensions/function-libraries/about-the-function-library-manifest.md): The manifest's top-level fields.
- [Function Reference](https://dev.wix.com/docs/site-extensions/function-libraries/function-reference.md): The fields that declare a function, its parameters, and its return value.
- [Function Library Resources Reference](https://dev.wix.com/docs/site-extensions/function-libraries/function-library-resources-reference.md): The fields that identify the library's implementation.
- [Editor React Types](https://dev.wix.com/docs/site-extensions/editor-react-components/editor-react-types/overview/about-editor-react-types.md): The TypeScript types you can use for function parameters and return values.

## See also

- [Function Libraries](https://dev.wix.com/docs/overview/extensions-framework/site-extensions/function-libraries.md)
- [About Function Libraries in Studio Two](https://dev.wix.com/docs/studio-two/code-your-site/code-model/function-libraries/about-function-libraries.md)