Google XML sitemap is the best way to let Google know about different pages and content of website and site owners and webmaster use this powerful tool get index by Google. They were working since 2005 from the time when they make this feature available and later introduced specialize sitemap formats that helps webmaster to add video, images, code, mobile URL and geographic content. Finally on 29th June 2010 Google had successfully introduced a single sitemap that accommodate different content types in a single file.
Here are the examples of different sitemap structure that used to specify different content type in a single Google XML sitemap.
<?xml version="1.0" encoding="UTF-8"?>
<video:title>Grilling tofu for summer</video:title>
Some old features will still remain same like you can include maximum 50,000 URL in a sitemap and sitemap site must not exceed 10 MB.
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