The "xml:" Namespace

This Version: May 21, 2001

Description

The namespace whose name is http://www.w3.org/XML/1998/namespace is bound by definition to the prefix xml: according to Namespaces in XML, W3C Recommendation 14 Jan 1999. Note that unlike all other XML namespaces, both the name and the prefix are specified; i.e., if you want XML 1.0 processors to recognize this namespace, you must use the reserved prefix xml:.

xml:lang and xml:space

As of the last update of this document, the XML 1.0 Specification defines two attribute names in this namespace:

xml:lang
Designed for identifying the human language used in the scope of the element to which it's attached.
xml:space
Designed to express whether or not the document's creator wishes white space to be considered as significant in the scope of the element to which it's attached.

xml:base

The XML Base specification describes a facility, similar to that of HTML BASE, for defining base URIs for parts of XML documents. It defines a single attribute, xml:base, and describes in detail the procedure for its use in processing relative URI refeferences.

Related Resources

Section 2.10 of the XML 1.0 specification describes the syntax and semantics of the xml:space attribute.

Section 2.12 of the XML 1.0 specification describes the syntax and semantics of the xml:lang attribute.

An XML Schema fragment is available which constrains the syntax of xml:lang and xml:space.

The value of the xml:lang attribute must be as specified by RFC 1766 or its successors.

The W3C XML Base specification for the xml:base attribute.

Language Codes for use in xml:lang

Language codes come in digraph (ISO 639) and alpha-3 (ISO 639-2) flavors. They may be modified by country codes (ISO 3166) and language identifiers registered with the Internet Assigned Numbers Authority.

The U.S. Library of Congress has been designated the ISO 639-2/RA for the purpose of processing requests for alpha-3 language codes comprising the International Standard, Codes for the representation of names of languages-- Part 2: alpha-3b code.

The Registration Authority for ISO 639 is Infoterm, Osterreichisches Normungsinstitut (ON), Postfach 130, A-1021 Vienna, Austria. Apparently, no official normative list is made available on the Web, but there is an unofficial list, "typed in by Keld.Simonsen@dkuug.dk 1990-11-30".

The ISO 3166 Maintenance Agency (ISO 3166/MA).

A directory of IANA language codes.