HTML and CSS Reference
CSS2, CSS2.1, CSS3, Drafts, Recommendations, Ack!
We're at a moment in time where the state of the CSS “standard,” while
active and exciting, can often be confusing. The W3C's CSS Working
Group consists of representatives from browser vendors and other tech-
nical experts who are actively writing and maintaining the specifications.
At first look, there are a lot of specification documents, and they're all at
different points in the process.
There are many states a specification moves through on its way to being
finalized, gathering comments and test implementations along the way:
■ Working Draft : A Working Draft (WD) is the earliest definition of the
specification. The document itself will often be loaded with notes,
questions, or incomplete references. Working Drafts are useful to see
what is ahead and for browser vendors to create test implementations.
There will be certainly be changes to the document and possibly to
individual property definitions in the future because no consensus on
the content of the document has yet been reached.
■ Last Call Working Draft : When issues, conflicts, and questions in the
Working Draft are resolved, there is a Last Call (LC) comment period
announced to solicit feedback on the draft.
■ Candidate Recommendation : After that Last Call period, a draft may
move onto a Candidate Recommendation (CR), and the working group
solicits test implementations from vendors to make sure what has
been proposed is workable.
■ Proposed Recommendation : To be a Proposed Recommendation (PR),
the specification is stable, and vendors have created interoperable
■ Recommendation : The bill has become a law—or a finalized
Recommendation (R) as it were.