Important terms related to Web Design & Development
XHTML stands for Extensible HyperText Transfer Protocol. It is a reformation of HTML as an XML vocabulary. XHTML is an XML application that specifies how XML can be used to describe a web page. XHTML documents look very similar to HTML documents, except they follow the stringent rules of XML (which include things like all tags must have a matching closing tag, attributes must be quoted, tags must be nested properly and there must be a root tag for the overall document)
XML stands for Extensible Markup Language. It is a markup language for writing other markup languages. XML is sometimes called a "meta" language because it describes how to write new languages. It allows for the creation of applications that are streamlined for the use of the owner.