Sitemap and other Tools

Sitemap is a well constructed XML file that specify list of contents at your website.

Google and other search engines CAN crawl you site without sitemap. (Reference: Do I need a sitemap?) However, it is a nice way to organize your contents and also a way to let search engine know about your new or possibly not well linked contents.

For detail, you can refer to http://www.sitemaps.org/  and for format of Sitemap XML http://www.sitemaps.org/protocol.html

And great article is at https://moz.com/blog/xml-sitemaps-guidelines-on-their-use