As you read the specification, you may find it enlightening to keep in mind the following principles that guided the design of HTML 4.0.
While most people agree that HTML documents should work well across different browsers and platforms, achieving interoperability implies higher costs to content providers since they must develop different versions of documents. If the effort is not made, however, there is much greater risk that the Web will devolve into a proprietary world of incompatible formats, ultimately reducing the Web's commercial potential for all participants.
Each version of HTML attempts to reach greater consensus among industry players so that the investment made by content providers will not be wasted and that their documents will not become unreadable in a short period of time.
HTML has been developed with the vision that all manner of devices should be able to use information on the Web: PCs with graphics displays of varying resolution and color depths, cellular telephones, hand held devices, devices for speech for output and input, computers with high or low bandwidth, and so on.
This version of HTML has been designed with the help of experts in the field of internationalization, so that documents may be written in every language and be transported easily around the world. This has been accomplished by incorporating [RFC2070], which deals with the internationalization of HTML.
One important step has been the adoption of the ISO/IEC:10646 standard (see [ISO10646]) as the document character set for HTML. This is the world's most inclusive standard dealing with issues of the representation of international characters, text direction, punctuation, and other world language issues.
HTML now offers greater support for diverse human languages within a document. This allows for more effective indexing of documents for search engines, higher-quality typography, better text-to-speech conversion, correct hyphening, etc.
As the Web community grows and its members diversify in their abilities and skills, it is crucial that the underlying technologies be appropriate to their specific needs. HTML has been designed to make Web pages more accessible to those with physical limitations. HTML 4.0 developments in the area of accessibility include:
Authors who design pages with accessibility issues in mind will not only receive the blessings of the accessbility community, but will benefit in other ways as well: well-designed HTML documents that distinguish structure and presentation will adapt more easily to new technologies.
The new table model in HTML is based on [RFC1942]. Authors now have greater control over structure and layout (e.g., column groups). The ability of designers to recommend column widths allows user agents to display table data incrementally (as it arrives) rather than waiting for the entire table before rendering.
HTML now offers a standard mechanism for embedding generic media objects and applications in HTML documents. The OBJECT element (together with its more specific ancestor elements IMG and APPLET) provides a mechanism for including images, video, sound, mathematics, specialized applications, and other objects in a document. It also allows authors to specify a hierarchy of alternate renderings for user agents that don't support a specific rendering.
Style sheets simplify HTML markup and largely relieve HTML of the responsibilities of presentation. They give both authors and users control over the presentation of documents --- font information, alignment, colors, etc.
Stylistic information can be:
The mechanism for associating a style sheet with a document is independent of the style sheet language.
Through scripts, authors may create "smart forms" that react as users fill them out. Scripting allows designers to create dynamic Web pages, and to use HTML as a means to build networked applications. The mechanisms provided to associate HTML with scripts are independent of particular scripting languages.
HTML features allow user agents to print a collection of documents in an intelligent manner based on descriptions of the relationships among documents acting as parts of a larger work.
This version of HTML has been designed to remain easy to learn and adequate for many common publishing needs. The language offers more complex constructs (e.g., forms, scripting) for more sophisticated tasks, but even these mechanisms will become easier to use as powerful HTML authoring tools flourish.
Beware - at the time of writing, some HTML authoring tools rely extensively on tables for formatting, which may easily cause accessibility problems.