XMLS

XML是eXtensible Markup Language，即可擴展標記語言，由SGML簡化而來，是許多置標語言（例如XMLs/RDF/RDFs/OWL等）的元語言。

運用語言

XMLS指XML Schema，即XML模式，用於定義XML詞表和結構用於機器識別和共享信息的定義語言。
Express shared vocabularies and allow machines to carry out rules made by people. They provide a means for defining the structure, content and semantics of XML documents. 【W3C consortium "XML schema"】 http://www.w3.org/XML/Schema
XML Schema is a language for describing the structure and constraining the contents of XML documents