RSS feeds are headlines that update themselves every so often. These headlines can be posted on websites, Moodle, or wherever. They can also be subscribed too so readers always get the latest news. If you are are running a blog for your class, using Wordpress, or Blogger for example, feeds are automatically created and you can find the links in the menu are at the bottom of the site. With these links you can post anywhere you want.
Just to give you an idea I am running a Wordpress blog about the best place to eat breakfast in Honolulu. Students post to this blog once a week. I wanted to make a feed with these postings. This was in fact automatically done with Wordpress under the meta options. I then added this feed to the front page of our Moodle site. Now my student are making their own headline news. Not bad for an ESL-College Prep class. You can also follow RSS Feeds for comments to blogs.