What is HTML5

HTML5 defines the fifth major revision of HTML, the core language of the World Wide Web. HTML5 includes all valid elements from HTML4 and XHTML 1.0.

A brief history

June 2004
The Web Hypertext Application Technology Working Group (WHATWG) was formed in response to the slow development of web standards monitored by the World Wide Web Consortium (W3C), and its decision to abandon HTML in favor of XML-based technologies. The WHATWG began focusing on HTML5.
January 2008
The WHATWG published the First Public Working Draft of the specification on 22 January 2008.
May 2009
The W3C allowed the XHTML 2.0 Working Group’s charter to expire and decided not to renew it. The W3C then began work on HTML5 as well.
January 2011
The WHATWG renamed its “HTML5” living standard to “HTML”. The W3C continues its project to release HTML5.
February 2011
The W3C extended the charter of its HTML Working Group with clear milestones for HTML5.
May 2011
The W3C HTML Working Group advanced HTML5 to “Last Call”, an invitation to communities inside and outside the W3C to confirm the technical soundness of the specification.
May 2012
The W3C HTML Working Group specification is back to “Working Draft” state at the W3C.
July 2012
The WHATWG and W3C decided on a degree of separation. W3C will continue the HTML5 specification work, focusing on a single definitive standard, which is considered as a “snapshot” by WHATWG. The WHATWG organization will continue its work with HTML5 as a “Living Standard”.
September 2012
The W3C proposed a plan to release a stable HTML5 recommendation by the end of 2014 and an HTML 5.1 specification recommendation by the end of 2016.

What does all of this mean?

HTML5 has had a difficult history – with two different organisations working to determine the overall direction and management of the specification. This means that there are two different versions of the HTML5 specification:

WHATWG specification

The WHATWG’s version of the specification is now called a “living standard”. The group intends to constantly develop the specification and so it will no longer be referred to using incrementing version numbers.The WHATWG has also included separate specifications that cover related technologies including Microdata, Canvas 2D Context, Web Workers, Web Storage, and others.View WHATWG’s various versions of the HTML spec for further information.

The W3C HTML5 working group specification

The W3C’s version of the specification also includes separate specifications for related technologies including Web Sockets, Webstorage, Workers, and others.View W3C’s HTML5 Editor’s drafts for further information.

Is there a difference?

The WHATWG version is less formal and more experimental.The W3C version is more rigidly defined and follows a clearly defined approval process.

HTML5 overall principles

The W3C HTML Working Group developed a series of principles for HTML5 in the areas of compatibility, utility and interoperability.
To support existing content and allow concepts to degrade gracefully.
To make sure that HTML can be used effectively for its many intended purposes.
To improve the chances of HTML implementations being truly interoperable.
Universal Access
To make sure that all HTML features are designed for universal access.
View W3C’s HTML design principles for further information.