In oder to subscribe to a category in a forum, click on category options at the top of the page and,
then click on subscribe to category. 

  

The page will then refresh and a message will appear at the top of the page,
notifying the user that the subscription has been successful.

 

   

Email Subsciption

When you reply to a topic or create a topic there is an option at the bottom of the page,
for Email Subcription.  This option is in the form of a checkbox and allows you to receive
an email everytime the topic is replied to.

 

 
RSS

Short for RDF Site Summary or Rich Site Summary, an XML format for syndicating Web content.
A Web site that wants to allow other sites to publish some of its content creates an RSS document,
and registers the document with an RSS publisher.

A user that can read RSS-distributed content can use the content on a different site. Syndicated content
includes such data as news feeds, events listings, news stories, headlines, project updates, excerpts from
discussion forums or even corporate information.

 

Opml

Opml is an XML-based format that allows exchange of outline-structured information,
between applications running on different operating systems and environments.

The Opml format is specially usefull for describing structered information like rss-subscriptionlists,
online-directories and other structured information you would like to share.