Steven Pemberton, CWI, Amsterdam and W3C
Chair, W3C HTML and Forms Working Groups
Editor in chief, ACM/interactions
The portion of the web that I represent today, is the user side:
So, let's go back to the early days
10 MHz, 1Mb, 20Mb
<title>My HTML File</title>
<h1>My first Webpage</h1> Welcome to my page!
Now let's fast forward 10 years:
1 GHz, 256Mb, 20Gb
When XML was designed...
This is OK. But beware: role model!
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title>Virtual Library</title> </head> <body> <p>Moved to <a href="http://example.org/">example.org</a>. </p> </body> </html>
Fast forward again
100GHz, 64Gb, 20Tb
<?xml version="1.1" encoding="UTF-8"?>
<?xml-stylesheet type="text/css" href="xhtml2.css"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 2.0//EN" "xhtml2.dtd"[
<!ATTLIST html
xmlns:xsi CDATA #FIXED "http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation CDATA #IMPLIED >
<!-- long list of redundant ATTLIST declarations for ID ... -->
]>
<html xmlns="http://www.w3.org/2002/06/xhtml2" xml:lang="en"
xmlns:ev="http://www.w3.org/2001/xml-events"
xmlns:xfm="http://www.w3.org/2002/01/xforms"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:svg="http://www.w3.org/2000/svg"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ev="http://www.w3.org/2002/xml-events" xmlns:mumble bla bla bla ginger
xsi:schemaLocation="http://www.w3.org/2002/06/xhtml2 xhtml2.xsd ...">
<head>
<title>My web page</title>
</head>
<body>
...
</body>
</html>
(Several things have been left out here for briefness)
In HTML:
<img alt="..." src="img.gif" longdesc="desc.html" usemap="#map"/>
Required by XLink:
<img xlink:type="extended" alt="..." > <xlink:locator role="src" href="img.gif"/> <xlink:locator role="longdesc" href="desc.html"/> <xlink:locator role="usemap" href="#map"/> <xlink:locator role="self" href="#xptr(here())"/> <xlink:arc from="self" to="src" show="embed" actuate="auto"/> <xlink:arc from="self" to="longdesc" show="new" actuate="html:user2"/> <xlink:arc from="self" to="usemap" show="html:imagemap" actuate="onRequest"/> </img>
<?xml version="4.1" encoding="UTF-8"?> <html profile="http://www.w3.org/profile/xhtml3"> <head> <title>....</title> etc.
Computers are getting more powerful
People aren't.