Here are some screenshots from the web interface.
This page shows the description for a mailing list. As you can see, I'm already subscribed. If i was not, I could enter my email address and would receive a confirmation mail with a link to be actually subscribed. Nothing more to do, whether you already are subscribed to some other list or not.
This shows the list of all mailing lists, using the great django admin interface. Note the filters on the right in the case you really have many lists.
The following three screenshots show you all what can be configured for a list, lot of them are not mandatory. A list can belong to none, one, or several topics.
Archive can be browsed by everybody (public), subscribers (private), or nobody. Here's an example showing a thread from a long time ago, in a private mailing list: