Google XML Sitemap

Google Sitemaps are XML files that list the URLs available on a site. The aim is to help site owners notify search engines about the URLs on a website that are available for indexing. Webmasters can include information about each URL, such as when it was last updated and its importance in the context of the site. You should try to make all pages on your site easily accessible to search engines without the use of google sitemaps. But there are situations when your site might benefit from Sitemaps Protocol like for instance if your site is built in rich AJAX or Flash, or if you have a large database driven site that isn’t well linked.