XML Sitemaps – How to:
Understanding XML Sitemaps
There are two types of sitemaps. One is a web page that people browse on a website to see an overview of the sites contents, the other is usually an XML file embedded into the root directory of the website (unseen to users) that assist search engines with what to index, how frequently and what priority to give to pages.
This website will tell you everything you need to know about the Sitemap XML protocol which has been recently agreed by Yahoo!, Google and MSN.
If you don’t have an XML sitemap, consider creating one and adding it to your website.
Everything you need to know about Sitemap at http://www.sitemaps.org.