There are many SEO tips and tricks that help in optimizing a site but one of those, the importance of which is sometimes underestimated is sitemaps. Sitemaps, as the name implies, are just a map of your site – i.e. on one single page you show the structure of your site, its sections, the links between them, etc. Sitemaps make navigating your site easier and having an updated sitemap on your site is good both for your users and for search engines.
Sitemaps are an important way of communication with search engines. While in robots.txt you tell search engines which parts of your site to exclude from indexing, in your site map you tell search engines where you’d like them to go.
Sitemaps are not a novelty. They have always been part of best Web design practices but with the adoption of sitemaps by search engines, now they become even more important. However, it is necessary to make a clarification that if you are interested in sitemaps mainly from a SEO point of view, you can’t go on with the conventional sitemap only (though currently Yahoo! and MSN still keep to the standard html format). For instance, Google Sitemaps uses a special (XML) format that is different from the ordinary html sitemap for human visitors.
Two types of sitemap ?
One might ask why two sitemaps are necessary. The answer is obvious – one is for humans, the other is for spiders (for now mainly Googlebot but it is reasonable to expect that other crawlers will join the club shortly). In that relation it is necessary to clarify that having two sitemaps is not regarded as duplicate content. In ‘Introduction to Sitemaps’, Google explicitly states that using a sitemap will never lead to penalty for your site.
Once you have created your two site maps, it is best to publish your ‘human’ sitemap under /sitemap.html and then you will need to upload your ‘spider’ sitemap to google.