What to expect from HTML5

Edward O’Connor

History

Archaic HTML — TimBL @ CERN
HTML < 3.2 — the IETF’s HTML WG
HTML 3.2, 4.0, and 4.01 — the W3C’s HTML WG
XML — W3C’s XML WG
XHTML 1.0, 1.1 — W3C’s HTML WG

Mismatch

HTML was defined as an SGML application
- Virtually all real-world markup is invalid
- Browsers parse HTML in a way very unlike SGML
XHTML is defined as an XML application
- Virtually all real-world XHTML is served as text/html
- (not to mention well-formedness errors)
- Browsers treat XHTML as HTML

Mismatch

Existing standards do not reflect reality.
Reality is billions of documents.
50, 100, 500 years from now, will we still be able to read our cultural output?

HTML5

HTML5 is a specification of HTML as it appears in the real world.

http://whatwg.org/html5 http://dev.w3.org/cvsweb/html5/spec/

With just this spec, you could build your own browser that works with today’s web, today’s content

HTML5 not defined in terms of SGML

Tag Soup

Sounds an awful lot like putting a big, fat, W3C stamp of approval on all the crappy tag soup out there…
Browser requirements are not author requirements

Browser requirements

Browsers have to support legacy content
- <table> for layout
- <b>ed and <br>eakfast
- etc.
Browsers have to interoperate
- what <b>does <i>this</b> look</i> like?
Defining interoperable error handling means no more reverse-engineering IE — Yay!

Doctype

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
          "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

No SGML means: no public identifier, no DTD

<!DOCTYPE html>

Triggers standards mode in Opera, IE, Firefox, and Safari.

Dropped elements

Authors aren’t allowed to use

<acronym> <basefont> <big> <center> <dir> <font> <frame> <frameset> <isindex> <noframes> <noscript> <s> <strike> <tt> <u>

But browsers are still required to handle them.

New elements

Document structure

<article> handy for blog archive pages
<section>
<header>
<footer>
<style scoped>

Many of the new elements came from studying real-world use of @class — how are authors compensating today for missing elements?

Document structure (con’t)

<aside>
<dialog>
<figure>
<nav>

2D Graphics API

<canvas>
clock from Mozilla’s <canvas> tutorial
You can use <canvas> today, in Firefox and Safari

Media

<embed> — browsers would have to support this anyway
<audio> and <video>

Web Forms 2.0

<input type={range,email,url,time,date,etc.}>
<output>
<input autofocus>
<input autocomplete>
etc.

You can help!

The W3C and the WHATWG are working on the same spec, and both working groups are open to the public!

BarCamp San Diego