B2B Integration : A Practical Guide to Collaborative E-commerce

Extensible Markup Language (XML) 161
However, XML is simply a data definition language, not a technology.
XML cannot by itself integrate different systems.
6.4.3. XML: A derivative of SGML
The parent of Extensible Markup Language (XML) is the Standard
Generalized Markup Language (SGML), an international standard for
the definition of device-independent, system-independent methods of
representing texts in electronic form. SGML is a meta-language, that is,
a means of formally conveying a language, for specifying the structure
and describing the content of documents. The use of SGML for encoding
electronic forms ensures their transportability from one hardware and
software environment to another without loss of information. SGML
enables a publishers to define their own document formats and create a
single document source that can be viewed, displayed, or printed in a
variety of ways.
XML is a sub-domain of SGML. The full specifications of SGML
have a lot of unused and optional features that over time have proven to
have a high cost/benefit ratio, especially for B2B type applications.
XML removes many of those arcane and seldom-used features of
SGML, making it easy to use for defining new document types and
creating their own tags while freeing them from the constraints of using
predefined tags.
6.4.4. Sample XML files
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