HTML and CSS Reference
In-Depth Information
What's Not in HTML5
As mentioned, HTML5 removes a number of tags that have been slated for removal for
some time. In most cases, the tags and attributes that were removed are either redundant
or have been replaced by CSS properties. For example, the
<acronym>
tag has been
removed because it serves the same purpose as the
<abbr>
(abbreviation) tag. The
bor-
der
attribute of the
<img>
tag has been removed because you can use the CSS
border
property to achieve the same effect.
However, some tags and attribute have been removed without equivalent replacements.
The biggest feature removed by HTML5 is frames. HTML5 supports the
<iframe>
tag,
which can be styled using CSS, but
<frameset>
,
<frame>
, and
<noframes>
have all been
removed. In the future, if you want to create a framed site in the traditional sense, you'll
need to use the HTML 4.01 Frameset or XHTML 1.0 Frameset DOCTYPEs.
Using HTML5
A lot of web designers are eager to dive in and start using all the new features in
HTML5. They require fewer browser add-ons, provide new functionality, and enable
designers to create simpler, more readable markup. The problem is that not even the most
recent browsers offer full support for HTML5, and older browsers don't support it at all.
Therefore, if you want a feature to be available to your full audience, even if you use
HTML5, you have to provide an alternate accommodation that works for other users.
That said, it's probably time to start migrating to the HTML5 future. This begins with
the HTML5 DOCTYPE, which I've used throughout the topic for pages that consist of
valid HTML5. It is
19
<!DOCTYPE html>
Here's the DOCTYPE for HTML 4.01:
<!DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 4.01//EN”
“http://www.w3.org/TR/html4/strict.dtd”>
As you can see, one of the charms of the HTML5 DOCTYPE is that it's short. It may be
the first DOCTYPE declaration that's easy to type in from memory. All current browsers
recognize the HTML5 DOCTYPE and render pages that use it in their standards-compliant
mode, rather than quirks modes that mimic older, incorrect implementations of standards
in old browsers.
The only catch is that if you're going to use the HTML5 DOCTYPE, be sure to avoid
using any tags or attributes that have been removed from HTML5.
