The version of html which we are currently using is HTML and it has not seen a major update in last 10 years although there has been so much development in UI in terms of technology and browsers.

W3C is working on next major release of HTML , keeping in tunes with the times and has released a draft version. HTML 5 defines the fifth major revision of the core language of the World Wide Web, HTML

The technical difference can be read from here HTML 5

One of the most important features which I liked about HTML5 was its database specification . This lets a web application create and use a local database, which means it can work without an internet connection, and even more importantly, it’s way faster than before. HTML5 is supposed to be disruptive and is already being used in Google.

Google has demoed the new version of gmail which is in HTML5 . Click here to see the demo

Firefox 3.5 supports HTML 5 audio and video with Ogg Theora

HTMl5 would bring much more power to the web and to the developers who definitely would bring some innovative applications