X Hits the Spot

A year or two ago, XML was heard about more often than it was seen, a technology that was sufficiently arcane enough to keep all but the most hardened geeks at bay. No more is this the case. Today, XML is most definitely in the mainstream, and proving its mettle by making all kinds of new and unique applications possible (witness the success of Amazon.com's AWS service, or the Google APIs, both based on XML technology).

XML isn't resting on its laurels, though. As the technology is becoming more and more popular, XML development groups operating under the aegis of the World Wide Web Consortium are rapidly inventing new and interesting ways to use it. One of the more interesting ideas is XForms, which uses XML to manage the display, input and processing of user-inputted data on the Web.

If you're at all serious about using XML, you're going to need to understand XForms. And over the course of this tutorial, I'm going to assist you in this endeavor by explaining the fundamentals of the XForms data model, together with some examples of how it can be used.

Before we get going, though, a few disclaimers:

First, I don't claim to be an expert on XForms. Much of the material in this tutorial is based on my own research with the XForms specifications and varied XForms implementations, or gleaned from late-night email conversations over beer and stale pizza. In other words, caveat emptor!

Second, as new XML standards are proposed and disposed, the material here may become invalid; you should always refer to the most current standard or recommendation for up-to-date information. This tutorial is based on the W3C's XForms 1.0 recommendation dated 14 October 2003, at http://www.w3.org/TR/2003/REC-xforms-20031014/.

Now that I have that off my chest, let's get started!