Introduction
What is Html5?
Html5 is the latest and most enhanced version of Html. It is the next major revision of the Html standard. Html5 is a standard for structuring and presenting content on the World Wide Web. Html5 is a cooperation between the World Wide Web Consortium (W3C) and the Web Hypertext Application Technology Working Group (WHATWG).
Html5 is designed to deliver almost everything you want to do online without requiring additional plugins. It does everything from animation to apps, music to movies, and can also be used to build complicated applications that run in your browser. Html5 is also cross-platform. The Html 5 working group includes AOL, Apple, Google, IBM, Microsoft, Mozilla, Nokia, Opera, and hundreds of other vendors.
Html5 is still a work in progress. However, all major browsers support many of the new Html5 elements and APIs
Supported Browser for Html5
Html5 is not yet an official standard, and no browsers have full Html5 support. The latest versions of Google Chrome 
, Mozilla Firefox 
, Apple Safari 
, and Opera 
all support many Html5 features and Internet Explorer 9.0 
will also have support for some Html5 functionality.
The mobile web browsers that come pre-installed on iPhones, iPads, and Android phones all have excellent support for Html5.
Html5 - New Features
Html5 introduces a number of new elements and attributes that helps in building a modern websites, features are -
New content specific elements like <header>, <footer>, <section>, <nav> and <article>.
New form controls where new attributes have been introduced for <input> tag like calendar, date, time, email, url, search
Persistent local storage to achieve without resorting to third-party plugins.
WebSocket a next-generation bidirectional communication technology for web applications.
Server-sent events which flow from web server to the web browsers and they are called Server-Sent Events (SSE).
Canvas is the new elements that supports a two-dimensional drawing surface with the help of JavaScript.
Audio and Video elements that embed audio or video on web pages without resorting to third-party plugins.
Geolocation that help to share visitor's physical location with web application.
Microdata help to create vocabularies beyond Html5 and extend web pages with custom semantics.
Drag and drop is help to move object in web page with more user friendly way.