Moreover, whenever your site gets updated, your sitemap notifies search engines about it. There are two types of audiences a sitemap is useful to – site visitors and web spiders, and there are also two types of sitemaps: HTML and XML sitemaps.
HTML sitemap is for visitors – it helps find information on the page, and it’s usually located in the website’s footer.
XML sitemap is for web crawlers – it tells them which parts of the site should be indexed as well as the hierarchy and priority of the site content. The instructions to the sitemap are provided in robots.txt file.