Extensible Markup Language (XML) Description

Subject: Extensible Markup Language (XML)

Date: 7 Apr 1997 05:53:35 GMT

From: bosak@boethius.eng.sun.com (Jon Bosak)

Newsgroup: comp.text.sgml



    ---------------------------------------------------------------------

XML is a new language for advanced Web applications proposed by a
working group of the World Wide Web Consortium (W3C).

A revised working draft of the XML syntax specification is now
available at

   http://www.w3.org/pub/WWW/TR/WD-xml-lang-970331.html

This draft replaces the previous one dated November 14, 1996.

PostScript and RTF versions of the new draft are available at:

http://sunsite.unc.edu/pub/sun-info/standards/xml/spec/xml-lang.ps.gz
http://sunsite.unc.edu/pub/sun-info/standards/xml/spec/xml-lang.ps.zip
http://sunsite.unc.edu/pub/sun-info/standards/xml/spec/xml-lang.rtf.gz
http://sunsite.unc.edu/pub/sun-info/standards/xml/spec/xml-lang.rtf.zip


BACKGROUND

Extensible Markup Language (XML) is a standardized text format
specially designed for transmitting structured data to Web
applications.  The new language addresses the needs of Web publishers
who encounter limitations in the ability of HTML to express structured
data.

XML differs from HTML in three basic ways:

1. Information providers can define new tag and attribute names at
   will.

2. Document structures can be nested to any level of complexity.

3. Any XML document can contain an optional description of its grammar
   for use by applications that need to perform structural validation.

XML has been designed for maximum expressive power, maximum ease of
implementation, and maximum teachability.  The XML character set is
Unicode.

XML is not backward-compatible with existing HTML documents, but
documents conforming to the W3C HTML 3.2 specification can easily be
converted to XML, as can documents conforming to ISO 8879 (SGML) and
documents generated from databases.

XML is not designed to be a replacement for HTML.  It is designed to
complement HTML by enabling a different kind of data to be exchanged
over the Web.

The current draft only addresses syntax, and consequently XML alone
can at present only be used for interprocess communication and for the
delivery of documents to specialized applications (or plug-ins) that
have been configured to interpret a particular XML grammar.  The first
draft of a companion specification for hypertext linking between XML
documents is scheduled for release April 9 at the Sixth World Wide Web
Conference.

----------------------------------------------------------------------
 Jon Bosak, Online Information Technology Architect, Sun Microsystems
     2550 Garcia Ave., MPK17-101, Mountain View, California 94043
 Davenport Group::SGML Open::NCITS V1::ISO/IEC JTC1/SC18/WG8::W3C XML
----------------------------------------------------------------------