A RSS (Real Simple Syndication) feed is a relatively new and easy way to distribute content on the Internet. It's useful to distribute messages to your customers avoiding spam filters. Typical uses include email newsletters and blogs. Similar to newsgroups, RSS feeds require a special “reader” like Google Reader to view messages.
The Database Feeds page dynamically generates an RSS feed. You'll be able to see the link to the RSS at the bottom of the page (some styles may not include this link).
You can use this link http://feedvalidator.org/ to validate the content of your RSS feed, once is valid you can include the Valid RSS Banner and the RSS icon.