IBM Generalized Markup Language

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Generalized Markup Language (GML) is a set of macros that implement intent-based markup tags for the IBM text formatter, "SCRIPT". SCRIPT is the main component of IBM's Document Composition Facility (DCF). A "starter set" of tags in GML is provided with the DCF product.

GML was developed in the 1960s by Charles Goldfarb, Edward Mosher and Raymond Lorie (whose surname initials were used by Goldfarb to make up the term GML [cite web|url=http://www.sgmlsource.com/history/roots.htm|year=1996|title=The Roots of SGML - A Personal Recollection|author=Charles F. Goldfarb|accessdate=2007-07-07] ).

GML simplifies the description of a document in terms of its format, organization structure, content parts and their relationship, and other properties. GML markup (or tags) describes such parts as chapters, important sections, and less important sections (by specifying heading levels), paragraphs, lists, tables, and so forth.

GML frees document creators from specific document formatting concerns such as font specification, line spacing, and page layout required by Script. Using GML, a document is marked up with tags that define what the text is, in terms of paragraphs, headers, lists, tables, and so forth. The document can then be automatically formatted for various devices simply by specifying a profile for the device. For example, it is possible to format a document for a laser printer or a line (dot matrix) printer or for a screen simply by specifying a profile for the device without changing the document itself.

A later and more extensive set of tags is provided by IBM's BookMaster product.

GML preceded and was one of the two sources that were used as the basis for the industry-developed Standard Generalized Markup Language (SGML), a set of rules for creating structured document description languages. The Extensible Markup Language (XML) was initially a streamlined and simplified development of SGML, but has outgrown its parent in terms of worldwide acceptance and support.

GML should not be confused with the Game Maker scripting language, or with the Geography Markup Language developed by the Open GIS Consortium.

A GML script example

:h1.Chapter 1: Introduction :p.GML supported hierarchical containers, such as :ol :li.Ordered lists (like this one), :li.Unordered lists, and :li.Definition lists :eol. as well as simple structures. :p.Markup minimization (later generalized and formalized in SGML), allowed the end-tags to be omitted for the "h1" and "p" elements.

ee also

* HyperText Markup Language
* Standard Generalized Markup Language
* XML

References

External links

* [http://publibfp.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/dsm04m00/CCONTENTS GML Starter Set User's Guide]
* [http://publibfp.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/dsm05m00/CCONTENTS GML Starter Set Reference]