From GroupScript documentation
GroupScript software provides two kinds of feeds- RSS and XML.
RSS feed is for site visitors who want an easy way to see new deals. Most browsers have integration for RSS feed aggregation but third party software can be used for this (e.g. Google Reader). RSS feed link is http://yoursite.com/index.php/frontend/feeds/rss
Our demo site's RSS feed is http://demo.groupscript.net/index.php/frontend/feeds/rss
XML feed is meant to be used by affiliates or deal aggregators. XML feed contains much more information on deals. XML feed link is http://yoursite.com/index.php/frontend/feeds/xml
For the list of available fields please see our demo site's XML feed: http://demo.groupscript.net/index.php/frontend/feeds/xml