HTML5 - World

The internet has changed a lot since HTML 4.01 became a standard in 1999.
Today, some elements in HTML 4.01 are obsolete, never used, or not used the way they were intended to. These elements are removed or re-written in HTML5.
To better handle today's internet use, HTML5 includes new elements for better structure, better form handling, drawing, and for media content.

New Semantic/Structural Elements

HTML5 offers new elements for better structure:

Tag	Description
<article>	Defines an article
<aside>	Defines content aside from the page content
<bdi>	Isolates a part of text that might be formatted in a different direction from other text outside it
<command>	Defines a command button that a user can invoke
<details>	Defines additional details that the user can view or hide
<summary>	Defines a visible heading for a <details> element
<figure>	Specifies self-contained content, like illustrations, diagrams, photos, code listings, etc.
<figcaption>	Defines a caption for a <figure> element
<footer>	Defines a footer for a document or section
<header>	Defines a header for a document or section
<hgroup>	Groups a set of <h1> to <h6> elements when a heading has multiple levels
<mark>	Defines marked/highlighted text
<meter>	Defines a scalar measurement within a known range (a gauge)
<nav>	Defines navigation links
<progress>	Represents the progress of a task
<ruby>	Defines a ruby annotation (for East Asian typography)
<rt>	Defines an explanation/pronunciation of characters (for East Asian typography)
<rp>	Defines what to show in browsers that do not support ruby annotations
<section>	Defines a section in a document
<time>	Defines a date/time
<wbr>	Defines a possible line-break

New Media Elements

HTML5 offers new elements for media content:

Tag	Description
<audio>	Defines sound content
<video>	Defines a video or movie
<source>	Defines multiple media resources for <video> and <audio>
<embed>	Defines a container for an external application or interactive content (a plug-in)
<track>	Defines text tracks for <video> and <audio>

The new <canvas> Element

Tag	Description
<canvas>	Used to draw graphics, on the fly, via scripting (usually JavaScript)

New Form Elements

HTML5 offers new form elements, for more functionality:

Tag	Description
<datalist>	Specifies a list of pre-defined options for input controls
<keygen>	Defines a key-pair generator field (for forms)
<output>	Defines the result of a calculation

Removed Elements

The following HTML 4.01 elements are removed from HTML5:

• <acronym>
• <applet>
• <basefont>
• <big>
• <center>
• <dir>
• <font>
• <frame>
• <frameset>
• <noframes>
• <strike>
• <tt>