Dynamic HTML: The Definitive Reference

A Fragmenting World

As you will see throughout this book, implementing Dynamic HTML applications that work equally well in both Navigator 4 and Internet Explorer 4 can be a challenge unto itself. Understanding and using the common-denominator functionality among the various pieces of DHTML will lead you to greater success than plowing ahead with a design for one browser and crossing your fingers about how things will work in the other browser.

One more potential gotcha is that the same browser brand and version may not behave identically across different operating systems. Navigator 4 is pretty good about maintaining compatibility when you open a document in operating systems as diverse as Solaris and Windows 3.1. The same can’t be said for Internet Explorer 4, however. Microsoft readily admits that some features (detailed in later chapters) are guaranteed to work only on Win32 operating systems (Windows 95, Windows 98, and Windows NT 4). Even features that should work on non-Win32 systems, such as style sheets, don’t always translate well to, say, the Macintosh version of IE 4.

If the inexorable flow of new browser versions, standards, and authoring features teaches us anything, it is that each new generation only serves to fragment further the installed base of browsers in use throughout the world. While I’m sure that every reader of this book has the latest sub-version of at least one browser installed (and probably a prerelease edition of a new version), the imperative to upgrade rarely trickles down to all the users of yesterday’s browsers. If you are designing web applications for public consumption, coming up with a strategy for handling the ever-growing variety of browser versions should be a top priority. It’s one thing to build a DHTML-based, context-sensitive pop-up menu system into your pages for IE 4 users. But what happens to users who visit with Navigator 4, or IE 3, or a pocket computer mini-browser, or Lynx?

There is no quick and easy answer to this question. So much depends on your content, the image you want to project via your application, and your intended audience. If you set your sights too high, you may leave many visitors behind; if you set them too low, your competition may win over visitors with engaging content and interactivity.

It should be clear from the sheer size of the reference section in this book that those good ol’ days of flourishing with only a few dozen HTML tags in your head are gone forever. As much as I’d like to tell you that you can master DHTML with one hand tied behind your back, I would only be deceiving you. Using Dynamic HTML effectively is a multidisciplinary endeavor. Perhaps it’s for the best that content, formatting, and scripting have become separate enough to allow specialists in each area to contribute to a major project. I’ve been the scripter on many such projects, while other people handled the content and design. This is a model that works, and it is likely that it will become more prevalent, especially as each new browser version and standards release fattens the following pages in the years to come.