Overview of HTML

Web documents are written using the Hypertext Markup Language (HTML). Originally there was no rigid definition of HTML and no mechanism for extending the language. This led to the situation where different groups added features that would work with their browsers but not necessarily with other browsers. (A notable example is that of fill-out forms; these were added by the NCSA for the X Windows version of Mosaic, but were not supported by other browsers - not even by Mosaic on other platforms.)

Recently there has been a move to standardize HTML. The original language has retrospectively been designated version 1.0 and version 2.0 will define current practice. Within version 2.0 there are three levels of features, 0, 1 and 2, which correspond to differing degrees of browser sophistication, level 0 being the simplest and level 2 the most complex. Version 2.0 is currently described in a draft Internet Request For Comments (RFC), which is expected to be finalized at the end of 1994.

HTML is a document type described in the Standard Generalized Markup Language (SGML), a system for formalizing the structure of documents and enabling documents to be interchanged between different document processing packages. Starting with version 2.0 HTML is formally defined as an SGML document type definition (DTD), which means that the definitive word on what constitutes legal HTML is embodied in an SGML definition. SGML is defined by an ISO standard (ISO 8879) and is described in The SGML Handbook[11] by Charles F. Goldfarb. Practical SGML[16] by Eric van Herwijnen is a good introduction to SGML.

Already there is discussion going on about version 3 of HTML, which will add new features to the language, such as tables, figures and mathematical formulae. This can probably be expected to appear some time in 1995.

Next: Getting started quickly Up: The Hypertext Markup Previous: The Hypertext Markup

[ITCP] Spinning the Web by Andrew Ford
© 1995 International Thomson Publishing
© 2002 Andrew Ford and Ford & Mason Ltd
Note: this HTML document was generated in December 1994 directly from the LaTeX source files using LaTeX2HTML. It was formatted into our standard page layout using the Template Toolkit. The document is mainly of historical interest as obviously many of the sites mentioned have long since disappeared.