Regular Language description for XML

REgular LAnguage description for XML (RELAX) is a specification for describing XML-based languages. A description written in RELAX is called a RELAX grammar.

RELAX Core has been approved as an ISO/IEC Technical Report 22250–1 in 2002 (ISO/IEC TR 22250-1:2002).<ref>Template:Cite web</ref> It was developed by ISO/IEC JTC 1/SC 34 (ISO/IEC Joint Technical Committee 1, Subcommittee 34 - Document description and processing languages).<ref>Template:Cite web</ref><ref>Template:Cite web</ref>

RELAX was designed by Murata Makoto.

In 2001, an XML schema language RELAX NG was created by unifying of RELAX Core and James Clark's TREX.<ref>Template:Cite web</ref><ref>Template:Cite web</ref><ref>Template:Cite web</ref> It was published as ISO/IEC 19757–2 in 2003.<ref>Template:Cite web</ref>