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Netscape Mozilla /
Microsoft Internet Explorer
HTML has now (July 1997) been drafted to the 4.0 (Cougar) specification. This document will summarize the features of this latest version of HTML.
In brief, HTML 4 includes advanced forms, frame improvements, table enhancements, objects, scripts, style, and more entities.
Since ancient times, people have used HTML to express thought and meaning in Web pages. Although formal specifications of HTML have been defined through the years, proprietary extensions to HTML have crept into prevailing practice. Each successive revision of the HTML standards has addressed the need to make HTML more expressive and, in some cases, formalize what had been occuring in practice.
HTML 4, new for the summer of 1997, represents a major advance in HTML implementation capabilities. HTML 4 also reinforces important design philosophies behind HTML.
Like treaties among warring countries, formal specifications don't always address all issues in the way some parties involved desire. HTML 4 thus represents a compromise among competing proprietary extensions. But the HTML 4 specification provides a framework for building hypertext on the Web at higher levels of sophistication. HTML 4 also sets out formal recognition of internationalization and ineroperability needs.
In practice HTML 4 will radically change accepted layout and alignment practices. HTML 3.2 formalized the TABLE element which has become a dominant tool for HTML implementation. The TABLE element supports the design concept of a grid as an organizing principle for page layout. As a result, the TABLE element has been used extensively on Web pages for layout control during 1996-1997. Many Web authoring tools rely on the TABLE element for alignment and element placement. This may change as style sheets become more widely used.
The themes of the HTML 4 revisions are: interoperability, internationalization, and accessiblity.
Interoperability is a goal for HTML documents. Developers should be able to create documents that work well in any Web browser. Moreover, the use of the Web is rapidly expanding to new contexts. Certainly, most use is through a Web browers installed on a personal computer. But considerations in the design of HTML 4 recognize that other devices may request and display Web information: cellular telephones, personal digital assistants, speech recognition devices, as well as computers with no graphical capability or with low bandwidth connections to the Web.
Because of the dominance of American English language used on the Web, internationalization has become an increasingly important goal for HTML documents. Specifically, HTML 4 addresses the character sets used in HTML documents. Versions of HTML prior to 4, relied on the ISO-8859-1 coded character set, which works well with Western European languages. Many people extended HTML on their own for other languages, so that, for example, Chinese and Japanese, could be displayed on Web pages. HTML 4 formalizes the recongnition of other languages by making the HTML document character set the ISO/IEC:10646 standard, the world's broadest standard for international languages, punctuation, and text direction (whether the text is read from left to right, right to left, top to bottom, or bottom to top).
Accessiblity is a goal for HTML documents in two contexts: human and machine. For humans, the principal method of perceiving HTML documents has been through text. However, HTML 4 has been developed with the idea of poviding better access to people through sound other other means (such as braille decoders). On the machine side, the accessiblity of HTML documents for non-graphical browsers as well as many different kinds of devices, previously mentioned, is a goal.
The HTML 4 specifications encourage Web developers to make their documents more accessible by using style sheets rather than tables for layout effects, making better use of text and aural descriptions of images for non-visual browsers, and better use of labels with HTML elements.
These are the new elements for HTML 4:
With every revision of HTML, there's a new set of elements that no longer are recommended because their functionality can be subsumed in the new HTML spects. For HTML 4, the deprecated elements and a brief explanation of why they are no longer recommended is:
These elements should not be used in HTML 4 documents: XMP, PLAINTEXT, and LISTING. Each was intended to render text which was intended to preserve line breaks and spacing (in computer code, for example). Instead, use the PRE (pre-formatted) element.
You can now align entries in a table based on certain characters. For example, you might want to line up data based on a decimal point or a dollar sign. Frames and rules are more flexible. Large tables, instead of taking the time to download all of their contents to be rendered, will be incrementally displayed. Support also has been added for scrollable contents and column-based defaults.
The relative unsophisticated capabilities of the FORM element in HTML 3.2 lead to widespread disappointment. After all, filling out forms is one of the most common online activities, yet the HTML 3.2 FORM element had little capability in this area.
In HTML 4, new attributes and elements allow Web developers to support more flexible and sophisticated entry options.
XX-ADD
Web developers can control the structure and layout of tables more precisely using HTML 4.
The first multimedia "object" that was embedded in an HTML document were images, using the IMG element. Recognizing the need for a general method to embed any kind of multimedia object, even some that have not yet been invented, the OBJECT element has been specified. The OBJECT element allows you to embed images, video, sound, mathematical expressions, as well as images and applets, in HTML documents.
Style sheets are the principal visual advance in the HTML 4 specifications. Style sheets boldly re-emphasize the separation of content and presentation that had become muddied in practice. Rather than rely on HTML elements such as TABLE or "tricks" of alignment, Web developers now can focus on creating information content and a separate set of stylistic information.
The use of scripting languages in HTML documents began during the Java craze of 1995-1996, when Netscape Communications, apparently seeking to cash in on the rocketing popularity of Java, renamed their proprietary "Netscript" extensions of HTML "JavaScript." JavaScript, which has nothing to do with the Java programming language, was a non-standard and often buggy and insecure method of implementing real-time interactivity on Web pages. The HTML 4 specification acknowledges the use of scripts and provides a new element, SCRIPT, that allows many kinds of scripting languages to be used on Web pages.
Printing HTML documents from a Web browser has been a commonplace practice for many years. However, printing the contents of a large Web site has been awkward. The user typically has visited each page of the Web site in turn and performed the "print" operation on the browser. HTML 4 makes it possible for Web developers to designate a print order for a collection of documents, making it possible for users to more easily create a dead tree-based version of a Web site.
Copyright © 1997 by John December. All rights reserved.