Sitemap

A sitemap is a blueprint of your website that help search engines find, crawl and index all of your website’s content. Sitemaps also tell search engines which pages on your site are most important. Though sitemap does not govern or mandate the search engines to index a certain page...rather it is a way of informing search engines that there's relatable content on the website that you would like to get indexed.
Sitemaps are of 4 main types:

• Normal XML Sitemap
• Video Sitemap
• News Sitemap
• Image Sitemap.

Sitemaps have to be on your technical on-page SEO checklist