Two standards bodies, the W3C and the WHATWG, have agreed to go their separate ways on the spec for HTML. There is little danger of a damaging fork in the road.
You may have read that the World Wide Web Consortium (W3C) and the Web Hypertext Application Technology Working Group (WHATWG) have agreed to disagree on how to handle the developing HTML5 standard. Well, in fact the two organizations have disagreed since the beginning on this question, but now they have formalized their incompatibility. The person editing both specs, Ian Hickson, announced on the WHATWG mailing list that he is dropping the editing duties at the W3C.
That sounds bad. Will the Web drift in diverging directions? The news seems to reinforce the old canard, "The nice thing about standards is that there are so many of them." But in fact this split is pretty much business as usual for the W3C and the WHATWG.
The W3C has always been about documenting compatible snapshots-in-time of standards as they emerge. The process of getting to those snapshots is slow; some consider it too slow for the fast-evolving Web. The WHATWG was formed in 2004 by browser developers from Apple, Mozilla, and Opera after the W3C abandoned ongoing work on an HTML specification and began to move towards an XML-based Web. The WHATWG worked on a spec they called HTML5, and in 2007 proposed to the W3C that that body's HTML working group adopt HTML5. The W3C agreed.
Ian Hickson telegraphed the changes that culminated in his recent resignation as W3C editor 18 months ago in a blog post at WHATWG. Hickson announced that what had heretofore been named "HTML5" would now be called simply "HTML" -- a living standard, not a snapshot fixed in time.
Meanwhile the W3C will carry on in its usual process to arrive at a snapshot to be called "HTML5." The standards body named not one but four editors to replace Hickson in working on the HTML5 spec.
The Verge asked Hickson about the likelihood of a damaging split in the standards produced by the two groups. His assessment: not likely.
It's certainly possible that the specs will fork, but it's unlikely, or at least, unlikely to happen in a way that is harmful. The WHATWG spec is going to match what implementations do regardless (that's what we do), and the W3C version has to pass the W3C Process, which requires proving interoperability.
Hickson added that any divergence was probably going to be a matter of one spec being more specific than the other in some particular area. He said that browser makers will simply know to use the more specific one.
We'll give the last word to Webmonkey.com, which describes the process as it has operated for the last few years:
A browser adds some shiny new feature, the WHATWG documents it, and other browsers implement their own versions. There's an awkward, sometimes frustrating period for Web developers while browsers tweak and refine their support, but eventually the dust settles and a new standard is added to the W3C's version. It may not be a completely ideal process, but it is what's managed to bring us this far.