Michael Mullany is vice president of products for ExtJS.
HTML5 Core vs. The HTML5 Family
When many folks say "HTML5" (particularly when this is followed with "will replace Flash"), they mean (or at least I think they mean), the broad collection of next-generation technologies that are now being implemented in the Webkit-based browsers (Safari and Chrome), Opera and Firefox. Some of these (like CS S3) were never part of the HTML5 standards process, and some of these (like web workers) were originally part of the spec but were spun out separately. We think the right way to refer to this collection is "the HTML5 Family." The family members of HTML5 (like all families) are in very different stages of maturity and implementation. Some are fully implemented in latest revision browsers, some may never see the light of day, and some will become altered beyond recognition before they show up in the mainstream. As mentioned before, the core W3C HTML5 spec is just one part of the collection of related technologies. I list the following specs as members of the HTML5 Family (more or less):
- The HTML5 spec
- Cascading Style Sheets Version 3 (CSS3)
- Web Workers
- Web Storage
- Web SQL Database
- Web Sockets
- Device API and File API
The Core HTML5 Spec
For users, the highest impact change in HTML5 is the addition of audio and video tags and a standard 2D bitmap drawing format (<canvas>). HTML5 audio and video tags allow playback without the use of plugins, and Canvas allows rich 2D bitmapped graphics.
There are many other features in the HTML5 spec, including a drag-and-drop API, cross-document messaging, persistent content caching directives, and user-editable content. Support for them is still being added to the latest browser revisions. Some parts may still end up being discarded before final implementation.
Finally, HTML5 removes many presentational markup elements that littered earlier HTML specs, like <center> and <font>. It also disallows direct table styling, and instead, requires the use of CSS. Frames are also officially eliminated.