The common handler implements the most common behavior on a web server.
It depends on the File sending and the Directory listing handlers. If the user requests for a directory, it is going to list its contents. But if the request if the a file, it is going to send it.
It accepts all the File sending and the Directory listing parameters.
This example sets the directory download up to allow everyone to browse its contents and download anything they want to.
Directory /download { Handler common }
It is also possible to specify some parameters, for example:
Directory /download { Handler common { HeaderFile /var/www/README } }