HTML5 tag support

HTML5 will be the new standard for HTML, XHTML, and the HTML DOM. Web pages will now be more semantic with the use of structure specific tags. Visual elements like rounded corners are now built in, and so is the ability to create drag and drop interactivity. Even though HTML5 is not fully supported in major browsers, there are those that are pushing forward and experimenting with its new features.
Some of the most interesting new features in HTML5:

• The canvas element for drawing

• The video and audio elements for media playback

• Better support for local offline storage

• New form controls, like calendar, date, time, email, url, search

• Client-side data storage and interactive documents

Here is the list of tags that are not supported in HTML5 :

<acronym>
<applet>
<basefont>
<big>
<center>
<dir>
<font>
<frame>
<frameset>
<noframes>
<s>
<strike>
<tt>
<u>
<xmp>

Some new tags introduced in HTML5 :

<article>     Defines an article
<aside>       Defines content aside from the page content
<audio>       Defines sound content
<command>     Defines a command button
<datalist>    Defines a dropdown list
<details>     Defines details of an element
<embed>       Defines external interactive content or plugin
<figcaption>  Defines the caption of a figure element
<figure>      Defines a group of media content, and their caption
<footer>      Defines a footer for a section or page
<header>      Defines a header for a section or page
<hgroup>      Defines information about a section in a document
<keygen>      Defines a generated key in a form
<mark>        Defines marked text
<meter>       Defines measurement within a predefined range
<nav>         Defines navigation links
<output>      Defines some types of output
<progress>    Defines progress of a task of any kind
<rp>          Used in ruby annotations to define what to show browsers that to not support the ruby element.
<rt>          Defines explanation to ruby annotations.
<ruby>        Defines ruby annotations.
<section>     Defines a section
<source>      Defines media resources
<summary>     Defines the header of a "detail" element
<time>        Defines a date/time
<video>       Defines a video