IBM Generalized Markup Language
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Generalized Markup Language (GML) is a set of macros (tags) for the IBM text formatter, "SCRIPT". SCRIPT is the main component of IBM's Document Composition Facility (DCF). A starter set version of GML is provided with the DCF product.
GML simplifies the description of a document in terms of its format, organization structure and content parts and their relationship, and other properties. GML markup (or tags) describe 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 capable 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), today's strategic set of rules for creating any structured document description language. This web page, as presented, is marked up with Hypertext Markup Language (HTML) which is an SGML application. 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.
[edit] External links
- HTML 4.01 Specification: Contains a lot of information about SGML.