Categories World Wide Web

By William Robert Stanek

People will look back on 1998 as the year the Web graduated, and one of the technologies taking us to the next level is the Cascading Style Sheets (CSS) specification. With Cascading Style Sheets, you can create Web pages with consistent colors, precise positioning of content, and other stylish embellishments. Like most other Web technologies, Cascading Style Sheets have gone through a metamorphosis in recent months, and what once was a simple fix for adding stylish content to a Web page is now a comprehensive solution for many types of structured documents.

Indeed, one of the goals of the latest style sheet specification is to define style elements that can be applied to structured documents of many different types, including HTML (HyperText Markup Language) and XML (Extensible Markup Language) pages. HTML, the markup language for traditional Web pages, is used to format text and multimedia to be viewed in browsers, such as Microsoft Internet Explorer and Netscape Navigator. XML is designed to structure data so that it can be transferred over a network. The latest CSS specification seeks to define style elements that can work with formatted text and multimedia as well as data structures.

The original implementation of the Cascading Style Sheets specification, designated as level 1 (CSS-1), has since been extended with several different proposals. One is the CSS-P (Cascading Style Sheets Positioning) proposal, which defines how content within a page can be precisely positioned. Both Internet Explorer 4.0 and Navigator 4.0 implement extensions for positioning content. While Microsoft chose a path similar to the CSS-P proposal, Netscape took a very different route--and the result is that there are several different ways of positioning content within a Web page.

All these options for positioning content have confused many Web developers. Fortunately, the CSS-2 (Cascading Style Sheets, level 2) proposal incorporates the core aspects of the positioning extensions exceedingly well. The result is that you'll soon have a standardized toolkit for positioning elements in a Web page. Beyond this, the level 2 proposal also includes quite a few surprises. Put all these changes together and you have a topic that could fill several books. So let's take a look at what's happening with style sheets and see if we can sort it all out.

William Robert Stanek is the author of several books, including Learn the Internet in a Weekend and Increase Your Web Traffic in a Weekend, published by Prima Publishing. His latest book, Server-Side JavaScript: The Definitive Guide, will be published by O'Reilly & Associates in June. He can be contacted at techwriting@tvpress.com.

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Published as Internet User in the 12/1/98 issue of PC Magazine.