Your support for our advertisers helps cover the cost of hosting, research, and maintenance of this FAQ
The original standard is Standard Generalized Markup Language, ISO 8879:1986. This is an ISO standard, so it's worldwide and international (see note below). XML itself is not an ISO standard: it doesn't need to be, as it is a) an application profile of SGML, enabled by the ‘WebSGML Adaptation’ Technical Corrigendum (2) to ISO 8879; and b) a W3C Recommendation, which means it has been through a formal process of approval roughly equivalent to standardisation.
On the other hand, HTML does have an ISO reference standard, ISO/IEC 15445:2000(E), but HTML is a concrete markup language, an actual application of SGML and XML, whereas XML and SGML are actually metalanguages used to define other markup languages.
Other XML applications like DocBook, JATS, and TEI have their own processes for development: DocBook, used for computer system documentation (including this FAQ), is standardised by the DocBook Technical Committee of OASIS (Organization for the Advancement of Structured Information Standards); Journal Article Tag Suite (JATS) is for scientific articles, and is developed by the National Information Standards Organization (NISO) and approved by the American National Standards Institute (ANSI); and the TEI Guidelines, widely used in the Humanities, are managed by the Technical Council of the Text Encoding Initiative (TEI).
The process of developing a standard document interchange specification (which is basically what these all are) is long and complex. Ken Holman has written an essay on how the OASIS technical committee process supports a group of members from an industry or economic sector in creating business exchange document specifications.
ISO standards like SGML are governed by the International Organization for Standardization in Geneva, Switzerland, and voted into or out of existence by representatives from every country's national standards body.
If you have a query about an international standard, you should contact your national standards body for the name of your country's representative on the relevant ISO committee or working group.
If you have a query about your country's representation in Geneva or about the conduct of your national standards body, you should contact the relevant government department in your country, or speak to your public representative.
The representation of countries at the ISO is not a matter for this FAQ. Please do not submit queries to the editor about how or why your country's ISO representatives have or have not voted on a specific standard.