There is often confusion between a “sitemap.html” file, which is used by site visitors as a navigation aid, and “sitemap.xml” file, which is used by search engines as a navigation aid. I should point out here that the robots.txt file is also a sitemap, but essentially backwards, since it tells the search engines where not to look. There are many other kinds of Sitemaps too, and for different purposes, as I will explain below.