HTML5
http://dev.w3.org/html5/spec/Overview.html[2010/6/23 21:58:49]
browsers to implement rendering engines that were incompatible with existing HTML Web pages, was the first result of this renewed interest. At this early
stage, while the draft was already publicly available, and input was already being solicited from all sources, the specification was only under Opera
Software's copyright.
The idea that HTML's evolution should be reopened was tested at a W3C workshop in 2004, where some of the principles that underlie the HTML5 work
(described below), as well as the aforementioned early draft proposal covering just forms-related features, were presented to the W3C jointly by Mozilla and
Opera. The proposal was rejected on the grounds that the proposal conflicted with the previously chosen direction for the Web's evolution; the W3C staff and
membership voted to continue developing XML-based replacements instead.
Shortly thereafter, Apple, Mozilla, and Opera jointly announced their intent to continue working on the effort under the umbrella of a new venue called the
WHATWG. A public mailing list was created, and the draft was moved to the WHATWG site. The copyright was subsequently amended to be jointly owned
by all three vendors, and to allow reuse of the specification.
The WHATWG was based on several core principles, in particular that technologies need to be backwards compatible, that specifications and
implementations need to match even if this means changing the specification rather than the implementations, and that specifications need to be detailed
enough that implementations can achieve complete interoperability without reverse-engineering each other.
The latter requirement in particular required that the scope of the HTML5 specification include what had previously been specified in three separate
documents: HTML4, XHTML1, and DOM2 HTML. It also meant including significantly more detail than had previously been considered the norm.
In 2006, the W3C indicated an interest to participate in the development of HTML5 after all, and in 2007 formed a working group chartered to work with the
WHATWG on the development of the HTML5 specification. Apple, Mozilla, and Opera allowed the W3C to publish the specification under the W3C
copyright, while keeping a version with the less restrictive license on the WHATWG site.
Since then, both groups have been working together.
The
HTML specification published by the WHATWG is not identical to this specification. At the time of this publication, the main differences were that the
WHATWG version included features not included in this W3C version: some features have been omitted, but may be considered for future revisions of HTML
beyond HTML5; and other features were omitted because at the W3C they are published as separate specifications.
A separate document has been published by the W3C HTML working group to document the differences between this specification and the language
described in the HTML4 specification.
[HTMLDIFF]
1.5 Design notes
This section is non-normative.
It must be admitted that many aspects of HTML appear at first glance to be nonsensical and inconsistent.
HTML, its supporting DOM APIs, as well as many of its supporting technologies, have been developed over a period of several decades by a wide array of
people with different priorities who, in many cases, did not know of each other's existence.
Features have thus arisen from many sources, and have not always been designed in especially consistent ways. Furthermore, because of the unique
characteristics of the Web, implementation bugs have often become de-facto, and now de-jure, standards, as content is often unintentionally written in ways
that rely on them before they can be fixed.
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