There is no central authority which grants or takes away permission read news. It requires a vote of the interested public. But this pretty much ensures that there are people out there interested in the topic. Other newsgroups are geographical, organizational, or commercial newsgroups. They may or may not be carried by your site.
Mailing lists work with normal electronic mail.
The same way that you send messages to your friends, you send messages to the mailing list. The mailing list software at the mailing list address takes care of making sure that everyone on the list gets the mail you send. You don't have to worry about it. In order to subscribe to a mailing list, you'll need to ask permission from the mailing list owner. Usually, the list owner delegates this responsibility to a computer program, which will let you in automatically.