Sitemaps were first introduced by Google in 2005, since then they have been implemented by all major search engines including (Yahoo, Bing and Ask).  Sitemaps allow you to inform search engines about content on your website.  The information you can communicate includes: when it was last updated, how often it changes, level of importance and related URLs.  Sitemaps allow search engines to intelligently crawl your site without exhaustively scanning every page for changes. The Internet Has Changed A lot has changed in search and in the technical infrastructure of the internet since 2005. ...

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