Apache Handler is an internal Apache representation of the action to be performed when a file is called. Generally, files have implicit handlers, based on the file type. Normally, all files are simply served by the server, but certain file types are "handled" separately. Based on either filename extensions or on location, handlers can be specified without relation to file type.
1. To add handler, select a Predefined Handlers from the select list and enter the File Extension and Save Changes
2. You may add 3 handlers at once
3. To delete it , tick on the Delete column and click Save Changes