Extensible Markup Language

XML

XML Stands for Extensible Markup Language. It is a markup language similar to HyperText Markup (HTML) that enables to store and exchange data in a structured format across different platforms and devices. XML Documents contain data as text in well-defined customized layouts by use of self-defining XML tags. These tags are extensible because the have the name given by a user and can be easily understood and customized by other people. These features have enabled XML to be widely accepted as a standard data-interchange format. World Wide Web Consortium (W3C) regularly develops new standard for XML usage by diverse software vendors and solution providers.

DTD

A DTD stands for Document Type Definition, which defines the structure of the content of an XML document, thereby storing the data in a consistent format. It defines the elements that are allowed to be present in the XML document, attributes of these elements, and their placement with relation to each other. A DTD also enables to specify whether an element is optional or not. An XML Document is considered valid, only if it confirms to DTD rules.

XSLT

XSLT stands for Extensible Stylesheet Language Transformations. It is an XML-based language that enables the transformation of an XML document into another XML or HTML document.