This sitemap is a file where you can list the web pages of your site.  This tells Google and other search engines about the organisation of your site content.

Search engine web crawlers like Googlebot read this file to more intelligently crawl your site.

You sitemap can provide valuable meta data associated with the pages you list.

Metadata is information about a webpage, such as when the page was last updated, how often the page is changed, and the importance of the page relative to other URLs in the site.