Standard Generalized Markup Language

[¦stan·dərd ‚jen·rə‚līzd ′märk‚əp ‚laŋ·gwij] (computer science) A system that encodes the logical structure and content of a document rather than its display formatting, or even the medium in which the document will be displayed; widely used in the publishing business and for producing technical documentation. Abbreviated SGML.

Standard Generalized Markup Language

(language, text)(SGML) A generic markup language forrepresenting documents. SGML is an International Standardthat describes the relationship between a document's contentand its structure. SGML allows document-based information tobe shared and re-used across applications and computerplatforms in an open, vendor-neutral format. SGML issometimes compared to SQL, in that it enables companies tostructure information in documents in an open fashion, so thatit can be accessed or re-used by any SGML-aware applicationacross multiple platforms.

SGML is defined in "ISO 8879:1986 Information processing --Text and office systems -- Standard Generalized MarkupLanguage (SGML)", an ISO standard produced by JTC 1/SC 18and amended by "Amendment 1:1988".

Unlike other common document file formats that represent bothcontent and presentation, SGML represents a document's contentdata and structure (interrelationships among the data).Removing the presentation from content establishes a neutralformat. SGML documents and the information in them can easilybe re-used by publishing and non-publishing applications.

SGML identifies document elements such as titles, paragraphs,tables, and chapters as distinct objects, allowing users todefine the relationships between the objects for structuringdata in documents. The relationships between documentelements are defined in a Document Type Definition (DTD).This is roughly analogous to a collection of fielddefinitions in a database. Once a document is convertedinto SGML and the information has been 'tagged', it becomes adatabase-like document. It can be searched, printed or evenprogrammatically manipulated by SGML-aware applications.

Companies are moving their documents into SGML for severalreasons:

Reuse - separation of content from presentation facilitatesmultiple delivery formats like CD-ROM and electronic publishing.

Portability - SGML is an international, platform-independent,standard based on ASCII text, so companies can safely storetheir documents in SGML without being tied to any one vendor.

Interchange - SGML is a core data standard that enablesSGML-aware applications to inter-operate and share dataseamlessly.

A central SGML document store can feed multiple processes in acompany, so managing and updating information is greatlysimplified. For example, when an aeroplane is delivered to acustomer, it comes with thousands of pages of documentation.Distributing these on paper is expensive, so companies areinvestigating publishing on CD-ROM. If a maintenance personneeds a guide for adjusting a plane's flight surfaces, aviewing tool automatically assembles the relevant informationfrom the document repository as a complete document. SGMLcan be used to define attributes to information stored indocuments such as security levels.

There are few clear leaders in the SGML industry which, in1993, was estimated to be worth US $520 million and isprojected to grow to over US $1.46 billion by 1998.

A wide variety tools can be used to create SGML systems. TheSGML industry can be separated into the following categories:

Mainstream Authoring consists of the key word processingvendors like Lotus, WordPerfect and Microsoft.

SGML Editing and Publishing includes traditional SGMLauthoring tools like ArborText, Interleaf, FrameBuilderand SoftQuad Author/Editor.

SGML Conversions is one of the largest sectors in the markettoday because many companies are converting legacy data frommainframes, or documents created with mainstream wordprocessors, into SGML.

Electronic Delivery is widely regarded as the most compellingreason companies are moving to SGML. Electronic deliveryenables users to retrieve information on-line using anintelligent document viewer.

Document Management may one day drive a major part of theoverall SGML industry.

SGML Document Repositories is one of the cornerstonetechnologies that will affect the progress of SGML as a datastandard.

Since 1998, almost all development in SGML has been focussedon XML - a simple (and therefore easier to understand andimplement) subset of SGML.

"ISO 8879:1986//ENTITIES Added Latin 1//EN" defines somecharacters. ISO catalogue entry.

SGML parsers are available fromVU, NL,FSU,UIO, Norway.

See also sgmls.

Usenet newsgroup: news:comp.text.sgml.

["The SGML Handbook", Charles F. Goldfarb, Clarendon Press,1991, ISBN 0198537379. (Full text of the ISO standard plusextensive commentary and cross-referencing. Somewhat cheaperthan the ISO document)].

["SGML - The User's Guide to ISO 8879", J.M. Smith et al,Ellis Harwood, 1988].

standard generalized markup language

Standard Generalized Markup Language