Webmasters are becoming increasingly aware of the power of the sitemap as an SEO tool, enabling search spiders to crawl more pages in less time with the end result of getting more or your links indexed faster. Because sitemaps require only those pages that have changes to be visited, valuable bandwidth can also be conserved.

The news that Google, Microsoft and Yahoo! have all finally agreed to support the single Sitemaps 0.90 protocol will only make this process ever easier. Given that, according to most sources, the big three have around 85% of the search engine market share, this announcement should not be undervalued. And by support, of course, they mean not only use sitemaps but also help with a joint development program. Think of it as being an open standard for SEO and you are not far off the mark.

Indeed, the protocol has been released under the Creative Commons license in the hope that other search engines will also join the party. You can find the full Sitemaps 0.90 protocol details at the jointly maintained sitemaps.org website.

So what, exactly, is a sitemap? Broken down to the basics it is nothing more complicated than an XML file listing the URLs for a website plus associated metadata such as that relating to the last update, regularity of changes and relative importance to other URLs at the same site. The XML schema for the Sitemap protocol consists of XML tags, and all the data values in a Sitemap must be entity-escaped and the file itself UTF-8 encoded. Other musts haves for a Sitemap include:

• Begin with an opening <urlset> tag and end with a closing </urlset> tag.
• Specify the namespace (protocol standard) within the <urlset> tag.
• Include a <url> entry for each URL, as a parent XML tag.
• Include a <loc> child entry for each <url> parent tag.

Because the sitemap supplements the web crawling process where pages are discovered from links internal and external to the site in question, it can help take the guesswork out of the link crawling process and ensure the most intelligent crawling route is taken. As sitemap.org admits, it does not guarantee pages get included in search engines, but the protocol does provide helpful hints for those crawlers to enable them to do a much better job of it.

Of course, the fact that you might have been submitting the same sitemap to Google, Yahoo and Microsoft without any problems already is beside the point, which is that now you can do so officially which should mean that more webmasters invest in doing just that. At least they can now do so just once, secure in the knowledge that it will cover that 85% search market share. To make things even easier, now that you know it will work across the board, you can use dedicated sitemap creation tools such as the GSite Crawler or the web-based XML-Sitemaps.com