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Glossary

XML : as it applies to web development technology

XML is an acronym for "Extensible Markup Language". In web technology, "extensible" describes something that is designed so that users or developers can expand or add to its capabilities. Extensibility and ease of use are the primary reasons why XML is so popular today. Knowing what extensible means we can say "XML is a Markup Language that can easily be used and expanded by application developers". Without XML, XHTML as you and I know it today would not exist.

XML is derived from Standard Generalized Markup Language (SGML), and was introduced with the guidance and endorsement of the World Wide Web Consortium (W3C) in 1996.