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## Resource: wix-media-backend

## Namespace: events

## Article: Introduction

## Article Link: https://dev.wix.com/docs/velo/apis/wix-media-backend/events/introduction.md

## Article Content:

# Introduction
Wix Media events are triggered when certain events occur with files created
 using the Media API. You can write event handlers that react to these
 events. Event handler functions receive data that corresponds to the event that
 has occurred. Use event handlers to create custom responses to media events.

 To add a media event handler, add an **events.js** file to the **Backend** section
 of your site if one doesn't already exist. All event handler functions for your
 site are defined in this file.

 Event handler functions are defined using the following pattern:

 ```javascript
 export function <wixAppName>_<eventName>(event) { }
 ```

 For example, an event handler that handles a file being uploaded to the
 Media Manager looks like this:

 ```javascript
 export function wixMediaManager_onFileUploaded(event) { }
 ```


 > **Note:** Backend events don't work when previewing your site.