Similar to Speech_Synthesis_Markup_Language
 - Web Services Description LanguageWeb Services Description Language
 - WS-AddressingWS-Addressing
 - WS-PolicyWS-Policy
 - WS-SecurityWS-Security
 - X3DX3D
 - XAdESXAdES
 - XCalXCal
 - XLIFFXLIFF
 - XML Metadata InterchangeXML Metadata Interchange
 - XML Paper SpecificationOpen XML Paper Specification
 - XML Process Definition LanguageXPDL
 - XML-RPCXML-RPC
- XML暗号化XML Encryption
 - XML署名XML Signature
- XML変換言語XML transformation language
 - XULXUL
 - アクセシブルな情報システムDigital Accessible Information System
 - WiXWiX
 - Text Encoding InitiativeText Encoding Initiative
 - FictionBookFictionBook
 - プロパティリストProperty list
 - W3C勧告
 - World Wide Web ConsortiumWorld Wide Web Consortium
 - Computer Graphics MetafileComputer Graphics Metafile
 - Document Object ModelDocument Object Model
 - Extensible Stylesheet LanguageXSL
 - Indexed Database APIIndexedDB
 - Portable Network GraphicsPNG