HTML sitemap is a page listing the pages of your site – often by section – and is meant to help users find the information they need.
XML Sitemaps – usually called Sitemaps, with a capital S – are a way for you to give Google information about your site. This is the type of Sitemap we’ll be discussing in this article.
In its simplest terms, a Sitemap is a list of the pages on your websites. Creating and submitting a Sitemap helps make sure that Search Engines (SE) knows about all the pages on your site, including URL’s that may not be discoverable by SE’s normal crawling process.