XML (Extensible Markup Language) is a W3C standard markup language and data format that defines rules for encoding documents in a way that is both human-readable and machine-readable. Originally published as a W3C Recommendation in 1998 (XML 1.0), XML provides the foundation for a wide ecosystem of related standards including XML Schema, XSLT, XPath, XQuery, SOAP, XHTML, SVG, RSS, Atom, and many domain-specific vocabularies. XML remains a core data interchange format for enterprise systems, web services, configuration, and document publishing.
Type: Standard Website: https://www.w3.org/XML/ Specification: XML 1.0 W3C Recommendation
| Spec | Status | Latest Edition |
|---|---|---|
| XML 1.0 | W3C Recommendation | Fifth Edition (2008) |
| XML 1.1 | W3C Recommendation | Second Edition (2006) |
| Namespaces in XML 1.0 | W3C Recommendation | Third Edition (2009) |
| XML Schema (XSD) 1.1 | W3C Recommendation | 2012 |
- Data Formats, Document, Markup Language, Standard, W3C, Web Services, XML
- Created: 2025
- Modified: 2026-05-03
Extensible Markup Language (XML) 1.0 is the foundational W3C Recommendation defining the syntax and processing model for XML documents.
Human URL: https://www.w3.org/TR/xml/
Extensible Markup Language (XML) 1.1 extends XML 1.0 to support newer Unicode versions and additional line ending characters.
Human URL: https://www.w3.org/TR/xml11/
Namespaces in XML 1.0 (Third Edition) defines a mechanism for qualifying element and attribute names in XML documents using URI references.
Human URL: https://www.w3.org/TR/xml-names/
XML Schema Definition Language (XSD) is the W3C Recommendation for describing the structure and constraints of XML documents using an XML-based grammar.
Human URL: https://www.w3.org/XML/Schema
| Schema | Description |
|---|---|
| xml-document-schema.json | Schema for XML document metadata and structure |
| xml-element-schema.json | Schema for XML elements, attributes, and children |
| Structure | Description |
|---|---|
| xml-document-structure.json | Canonical structural reference for XML documents |
| Context | Description |
|---|---|
| xml-context.jsonld | JSON-LD context mapping XML vocabulary to W3C and schema.org terms |
| Example | Description |
|---|---|
| xml-document-example.json | Example XML document metadata |
| xml-element-example.json | Example XML element representation |
| File | Description |
|---|---|
| xml-vocabulary.yml | Normative vocabulary for XML specification terms, constructs, and related standards |
FN: Kin Lane
Email: kin@apievangelist.com