Google has a method for improving the indexing of websites which are difficult to crawl naturally, allowing site owners to specify, with greater accuracy than before, which pages are higher priority and when pages are likely to change. While “natural” crawling is desirable, for some sites it just doesn’t work that well.
To tell Google about your sitemap, you must create it using a very specific format and follow a very specific procedure. Any mistake will cause Google to exclude the URL from the sitemap (and very possibly the Google index)
Sitemaps are one of the most exciting changes to happen at Google recently, and it will likely create a new competitive advantage for those who choose to use them.
Now, the XML format for sitemaps has been widely adopted and you can get improved bang-for-your-buck from sitemaps. In fact, it’s possible to tell the search engines exactly where your sitemap is using your .htaccess file. If this is foreign to you, don’t worry – I can explain.