Publishers of technology books, eBooks, and videos for creative people

Home > Articles > Web Design & Development > Usability

Web Design Reference Guide

Hosted by

What Does It Mean to Be Standards-Compliant?

Last updated Oct 17, 2003.

By Molly Holzschlag

So what does it mean to be standards-compliant? For those of us working in the realm of markup, it comes down to two very important issues: Conformance and Validation.

The Web markup and technologies we use—such as HTML, XHTML, and CSS—all have associated specifications for each of the language versions within that language. HTML, for example, has specifications from its very first incarnation through to HTML 4.01, the last specification available to HTML. XHTML has two primary specifications for standard Web markup use: XHTML 1.0 and XHTML 1.1. XHTML 2.0 is being worked on currently. CSS is in its second version, CSS2, with work on CSS3 well underway.

In order to be standards-compliant in the context of these languages, you must select a specific language and language version and write your documents in conformance with the specification as laid out by the W3C. What's interesting about this is that many Web professionals don't realize that just because a language version is a recommended version (at this writing, XHTML 1.1 is the recommended specification for authoring Web documents) doesn't mean it's a requirement. You can write conforming, standards-compliant documents in HTML 3.2 if you wish; the point is that you comply with the specification for that language and do not use any elements, attributes, events, characters, or structural components not allowed in that specification.

The single most effective way of ensuring compliance with W3C specifications is to validate your documents. The W3C has validation tools that you can use to achieve this. You'll find more information about these tools in the resources section later in this guide.