HTML5

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HTML5 is the next generation hypertext markup language standard developed by the World Wide Web Consortium. It is used by web programmers and designers -- typically in conjunction with JavaScript and CSS -- to lay out web pages, which people can then view in web browsers. As of July 2010, HTML5 is still not widely supported nor standardized, though browsers such as Google Chrome [1], Apple Safari [2], and Mozilla Firefox[3] have implemented various parts of the language. This unofficial status will likely persist for some years still, with the W3C currently expecting HTML5 to become a recommended technology in 2012 and a full standard not before 2022.

HTML5 represents an important step forward technologically, as it gives web developers greater capabilities and more flexibility in interacting with the underlying operating system. One important new capability is offline storage, which allows sites to better handle persistent sessions for their users. For example, if a user is editing a document in an online web editor, HTML5 allows some portion of the state associated with the document to be saved onto the user's computer -- rather than saving all of it to the server, as is currently done. This reduces the server load, and also provides a faster, more responsive experience for the user, as less data needs to be transferred over the network. Other new capabilities include a multipurpose graphical element called canvas, as well as native embedding of video and audio.

HTML5 also is a milestone politically and socially in the web world. As the web has evolved, many vendors have created proprietary technologies to enable greater functionality for their applications. Some of the most important include Adobe's Flash plugin, as well Microsoft's Silverlight and their browser Internet Explorer. Internet Explorer has a notable reputation for employing non-standard extensions to web technologies. While such innovations enable a richer user experience, they also fragment development, and make cross-browser compliance challenging for developers. HTML5 offers the opportunity to continue to support advanced interface demands, but to do so in an open, community-approved way. Indeed, in the words of Ian Hickson, one of the designers at W3C, "One of our goals [for HTML5] is to move the Web away from proprietary technologies." Such a step would lay the groundwork for the web's increasing dominance over the next decade.

Implications and Importance

HTML5 is an important extension to the current web development toolkit, both from a technical perspective and from a sociopolitical standpoint.

Social and Political Importance

Tim Berners-Lee: "HTML 5 is still a markup language for webpages, but the really big shift that's happening here—and, you could argue, what's actually driving the fancy features—is the shift to the Web [supporting applications]."

Language Details

Evolution from HTML4

The W3C standards organisation has published both a document containing the specifications of HTML5 and also one on how the specification differs from the now mature and more widely used HTML4 (Note that the HTML5 specification is a working draft and is subject to changes). Ian Hickson, a researcher at Google is the editor of the working draft and the W3C HTML Working Group is the W3C working group responsible for this specification's progress. Discussion of the specification also takes place among the WHATWG(Web Hypertext Application Technology Working Group) community. As per the published draft document (as of 02 Aug 2010), in addition to several new elements which include tags for multimedia content such as video and audio among others, there has been addition (and deprecation) of several attributes of various existing elements of the HTML4 specification.

Controversy over codec used for the <video> element

The HTML5 specification is such that it enables developers to use non-proprietary video codecs of their choice for the video tag. Popular video codecs of choice include the open source Ogg-Theora and h.264 codecs. However, there has been dispute over the default codec to be used. The open source community stands by and insists making Ogg-Theora the default codec due to its lesser patent regulations and licensing advantages. On the other hand, Apple, Adobe and Google citing quality concerns and other issues opposes the widespread adoption of Ogg-Theora causing browsers like Google's Chrome and Apple's Safari to be bundled with support for h.264 and Mozilla's Firefox supporting the Theora codec.