20 Essential Things to Know About the HTML5 Web Language

by Darryl K. Taft

The HTML5 specification defines the fifth major revision of the core language of the World Wide Web: the Hypertext Markup Language (HTML), also known as the lingua franca of the Web. The Web Hypertext Application Technology Working Group (WHATWG) started work on the HTML5 specification under the name Web Applications 1.0. As of October 2009, the specification is in the “Last Call” state at the WHATWG.

The HTML5 specification is not expected to be finalized until 2022, although work on the spec began in the mid-2000s. HTML4 was published in 1999.

Work on HTML5 began in June 2004, and the specification is a joint effort between the World Wide Web Consortium HTML Working Group (W3C HTML WG) and the WHATWG.

Ian Hickson, editor of the HTML5 specification, said he expects the specification to reach the W3C Candidate Recommendation stage during 2012 and W3C Recommendation in 2022. However, many parts of the specification are stable and may be implemented in products now.

According to Hickson, the timeline for delivery of the HTML5 specification is: • First W3C Working Draft in October 2007 • Last Call Working Draft in October 2009 • Call for contributions for the test suite in 2011 • Candidate Recommendation in 2012 • First draft of test suite in 2012 • Second draft of test suite in 2015 • Final version of test suite in 2019 • Reissued Last Call Working Draft in 2020 • Proposed Recommendation in 2022

HTML5 replaces HTML4, DOM2 HTML and XHTML 1.

In addition to specifying markup, HTML5 specifies scripting application programming interfaces (APIs). There are also new APIs, such as:• The canvas tag for immediate mode 2D drawing • Timed media playback • Offline storage database • Document editing • Drag-and-drop • Cross-document messaging • Browser history management • MIME type and protocol handler registration

HTML5 aims to reduce the need for proprietary plug-in-based rich Internet application (RIA) technologies such as Adobe Flash, Microsoft Silverlight and Sun JavaFX, though it would take many years to do so. HTML4 did not allow the embedding or control of multimedia content, whereas HTML5’s new audio and video elements enable developers to embed and control multimedia content without Flash.

HTML5 features such as Canvas, local storage and Web Workers enable developers to leverage the browser in ways earlier technology did not allow. Opera Software has been viewed as a leader in implementing HTML5 technology in its browser.

HTML5 technologies such as Canvas, for 2D drawing on a Web page, are finding their way into offerings from companies like Apple, Google and Mozilla.

HTML5’s local storage capability enables users to work in a browser when a connection drops, and the Web Workers technology makes applications responsive by pushing long-running tasks to the background.

All the major browser vendors—Mozilla, Opera, Microsoft, Apple and Google—are involved in shaping the HTML5 spec and are implementing support for it, despite the spec not being finalized.

Google’s Chrome browser has some HTML5 capabilities, such as video tags. Thus far, Google Chrome, Apple Safari, Opera and Firefox support HTML5 video. However, Opera and Firefox do not support the proprietary h.264 codec used for video players such as those from YouTube and Vimeo. Meanwhile, Microsoft’s Internet Explorer does not yet support HTML5 video. However, IE users can take advantage of HTML5 video by installing Google’s Chrome Frame open-source plug-in.

Microsoft has begun implementing parts of HTML5 in Internet Explorer 8. The software giant is adding such HTML5 features as local storage, AJAX navigation and mutable DOM prototypes.

YouTube and Vimeo has announced support for HTML5 video.

HTML5 has offline features similar to Google Gears, which enabled Google to shelve Gears in lieu of HTML5.

HTML5’s Web Sockets API enables two-way communication with a server so developers can implement games, chatting, remote controls and more.

HTML5 delivers: a new, sensible tagging strategy; localized databases; rich animations without plug-ins; and real apps in the browser, among other things.Link to related post: http://www.webmonkey.com/blog/How_HTML_5_Is_Already_Changing_the_Web

Palm’s webOS supports the HTML5 database object and Palm also supports HTML5-based maps on the Palm Pre.

After HTML5 is released the spec will switch to an non-versioned development model for the subsequent release. .Link to related post: http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2010-January/024708.html