HTML 5 TAGS Browser support

HTML 5:
  The below tags which are comes with HTML5 and which are supported in All Major browsers and not supported with.

Tags/Attributes	Browser support
contenteditable	All Browsers
contextmenu	present not supported any browser
accessKey	Not supported by Opera
draggable	IE8 and earlier versions, safari 5.1.2 Not supported

Contenteditable in HTML

Contenteditable :  It is new in HTML 5. This Attribute is supported in all major browsers. The contenteditable attribute specifies whether the content of an element is editable or not.

Syntax: < element contenteditable="true|false|inherit">

The attribute values of this contenteditable are true, false, inherit ( inherit specifies that the element is editable if its parent is)

Access Key in HTML

Access Key: To specify a shortcut key to access/focus a specific element in your HTML page use <accessKey>

This accessKey attribute works in all major browsers except Opera.

In HTML 5 the accessKey attribute can be used to any HTML element (it will validate on any HTML element.).

In HTML 4 the accessKey attribute can be used with <a> , <area> , <button> , <input> <label> ,  <legend> , <textarea>

The syntax:     <element accessKey="character">

HTML5 Introduction

HTML5 is the next major revision of the HTML standard superseding HTML 4.01, XHTML 1.0, and XHTML 1.1. 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).

The new standard incorporates features like video playback and drag-and-drop that have been previously dependent on third-party browser plug-ins such as Adobe Flash, Microsoft Silverlight, and Google Gears.
Browser Support:

The latest versions of Apple Safari, Google Chrome, Mozilla Firefox, 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.

New Features: HTML5 introduces a number of new elements and attributes that helps in building a modern websites. Following are great features introduced in HTML5.

• New Semantic Elements: These are like <"header">, <"footer">, and <"section">
• Forms 2.0: Improvements to HTML web forms where new attributes have been introduced for <"input"> tag.
• Persistent Local Storage: To achieve without resorting to third-party plugins.
• WebSocket : A a next-generation bidirectional communication technology for web applications.
• Server-Sent Events: HTML5 introduces events which flow from web server to the web browsers and they are called Server-Sent Events (SSE).
• Canvas: This supports a two-dimensional drawing surface that you can program with JavaScript.
• Audio & Video: You can embed audio or video on your web pages without resorting to third-party plugins.
• Geolocation: Now visitors can choose to share their physical location with your web application.
• Microdata: This lets you create your own vocabularies beyond HTML5 and extend your web pages with custom semantics.
• Drag and drop: Drag and drop the items from one location to another location on a the same webpage.
• Backward Compatibility

HTML5 is designed, as much as possible, to be backward compatible with existing web browsers. New features build on existing features and allow you to provide fallback content for older browsers.

It is suggested to detect support for individual HTML5 features using a few lines of JavaScript.