The easiest way to learn is to simply search it and read one of the many many posts that are available on the subject.
for example look at my RSS http://www.downloadvyp.com/feed/rss.html .you see,there are my latest added articles,in a simple way view.that page will change every time i add an article,without me having to do something
it is page that is crawled by search engines means it a page of your web that is used for SEO by search engines.