XML - (Extensible Markup Language) - XML enables more complex interactivity in regard to digital content. It's a markup language for documents containing structured information. XML was needed as SGML and HTML are not as suited for that. www.goxml.com is an XML context-based search processor. It can be used to create an unlimited number of your own custom tags and attributes versus HTML which have tags that have pre-defined and specific tasks.
http://en.wikipedia.org/wiki/Xml http://xml.coverpages.org/xml.html#bhtml http://informitv.com/glossary/xml 

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