What are Sitemaps?
A sitemap is a list of pages of a website to crawlers or users. Sitemaps are mainly of two types - one for the crawler and another for the users.
For the crawlers we use XML file and for the users we use HTML. We can view sitemaps of our blogs, websites in wordpress etc. To view the Sitemap of your website you can write following in address bar
Website name/sitemap.xml
which is for the crawler
Website name/sitemap.html
which is for the users