Extensible Markup Language (XML) can be termed as a standard or a set of rules that govern the procedure of encoding documents into an electric format. It has a very close relationship with HTML in the internet usage.
XML is responsible only for defining the structure of the web document. However, it has nothing to do with how the document will be displayed. HTML handles the displaying of the document instead.
This language defines no usable elements or tags. The user has the freedom to create any tag to describe the tags that are present in the XML document. However, you need to follow the correct structure in order to take advantage of this feature.
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XML Schema Document (XSD) is one of various XML schema languages. It defines what could be included inside the page. One of the major benefits of having well defined tags and elements is that the information in the document will be properly interpreted.
XSD’s biggest strength is that it is written in the XML. So, those who are already familiar with XML don’t need to learn another language. An XSD follows the HTML structure.
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