HTML and CSS Reference
For completeness, here are some of the most interesting fea-
tures of HTML5 that, for reasons of page count or lack of imple-
mentation, aren't discussed further.
Of course <embed> is well-known and has been used for years,
but was always an outlaw element that never validated. But like
that other outlaw, Robin Hood, it was widely supported because
it performed a useful function: It's the only way to get plugins
such as Flash to work reliably in all browsers, which explains
its overwhelmingly common usage (see 2008 stats at http://
there's no reason to keep it from validating. HTML5 paves that
particular cowpath and inally includes it into the formal lan-
But hang on. Isn't HTML5 supposed to replace all these plugin-
based technologies? Contrary to the sensationalist headlines of
some journalists, HTML5 won't magically replace plugins over-
night, and now we can embed them into HTML5 without incur-
ring the wrath of the validator.
This element, which is already well supported in all browsers
other than the big IE elephant in the room, is used in situa-
tions where your form needs to send a public key. Take a look
at http://en.wikipedia.org/wiki/Public_key to learn more about
And if you're still lost, you don't actually need this element!
These are exciting elements that allow you to deine toolbars or
context menus for your application, with icons and associated
commands that execute scripts when activated. They're cooler
than a bucket full of Lou Reeds. However, no browser yet sup-
ports them, so we don't discuss them further.