An RSS feed is a way for you to keep up to date with changes on a website. In the case of the LMF the changes are new files shared with a group. You can subscribe to a feed, which is similar to bookmarking it, and every time you look at your subscription you see the latest news for that feed.
Both Internet Explorer and Firefox support RSS feeds.
Podcasts are an extension of RSS feeds, where you can see the latest music and video files from a website of news. You subscribe to a podcast in the same way that you subscribe to an RSS feed. If you use a media player that supports podcasts, such as iTunes, it will automatically download the music and media files for you.
You can mix music and video files in an RSS feed with normal files like documents but anyone subscribing to it as a podcast may only see the music and video files.
You will now see on the information screen for a group, the feed iconand the words "RSS/Podcast feed" and that's your feed!