What is XML how to implement and when to use it

XML (Extensible Markup Language) is a markup language and was designed to describe structured data and information and the format is human-readable and machine-readable. You must create your own tags because XML tags are not predefined.
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How to make : Website and Blogspot XML sitemap

An XML sitemap is a file which you can write down all the URL web pages of your site to tell search engines about the page structure of your site contents. Search engine crawlers like Bingbot, Googlebot, YandexBot, Baidu Spider, etc read the XML file you've uploaded it into your host server and crawl your site. For Blogger/Blogspot just insert these simple parameters:

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