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## Resource: Introduction

## Article: Introduction REST

## Article Link: https://dev.wix.com/docs/api-reference/assets/http-functions/rest/introduction.md

## Article Content:

# About HTTP Functions

[HTTP functions](https://dev.wix.com/docs/velo/velo-only-apis/wix-http-functions/introduction.md) let you expose the functionality of a Wix site as various APIs. If you’ve added custom functionality to a site with code and want to use it in an app, you can expose HTTP functions and call these APIs in your code. 

Use the HTTP Functions API to call your site’s HTTP functions with an [authentication context](https://dev.wix.com/docs/api-reference/assets/http-functions/sdk/authentication-context.md). The authentication context provides information about who is calling an API. This means you can use functions that return different responses based on the caller, such as [`getCurrentMember()`](https://dev.wix.com/docs/sdk/backend-modules/members/members/get-current-member.md), within your HTTP functions.

## Before you begin

It's important to note the following points before you begin to code:

- Create an [access token](https://dev.wix.com/docs/rest/app-management/oauth-2/introduction.md) or an [API Key](https://dev.wix.com/docs/rest/articles/getting-started/api-keys.md) to authorize API calls and to provide authentication context to your site’s HTTP functions.

## Learn more about custom site APIs and HTTP functions
- [About custom site APIs](https://dev.wix.com/docs/develop-websites/articles/coding-with-velo/integrations/exposing-services/about-custom-site-apis.md)
- [Write an HTTP Function](https://dev.wix.com/docs/develop-websites/articles/coding-with-velo/integrations/exposing-services/write-an-http-function.md)
- [Methods for HTTP Functions](https://dev.wix.com/docs/develop-websites/articles/coding-with-velo/integrations/exposing-services/methods-for-http-functions.md)