First Public Working Draft: HTML Design Principles

W3C announced that the HTML Working Group has published a First Public
Working Draft for "HTML Design Principles." This document describes the
set of guiding principles used by the HTML Working Group for the
development of HTML5, expected to define the fifth major revision of
the core language of the World Wide Web. These design principles are an
attempt to capture consensus on design approach in the areas of
compatibility, utility, interoperability, and universal access. From
the Introduction: "In the HTML Working Group, we have representatives
from many different communities, including the WHATWG and other W3C
Working Groups. The HTML 5 effort under WHATWG, and much of the work
on various W3C standards over the past few years, have been based on
different goals and different ideas of what makes for good design. To
make useful progress, we need to have some basic agreement on goals
for this group. These design principles are an attempt to capture
consensus on design approach. They are pragmatic rules of thumb that
must be balanced against each other, not absolutes. They are similar in
spirit to the TAG's findings in Architecture of the World Wide Web, but
specific to the deliverables of this group. Conformance for Documents
and Implementations: Many language specifications define a set of
conformance requirements for valid documents, and corresponding
conformance requirements for implementations processing these valid
documents. HTML 5 is somewhat unusual in also defining implementation
conformance requirements for many constructs that are not allowed in
conforming documents. This dual nature of the spec allows us to have
a relatively clean and understandable language for authors, while at
the same time supporting existing documents that make use of older or
nonstandard constructs, and enabling better interoperability in error
handling..."