HTML5 is an attempt by the Web Hypertext Application Technology Working Group (WHATWG) and the World Wide Web Consortium (W3C) to create a single markup language for the World Wide Web, that combines the ongoing development of:
By combining all the above markup languages into a single markup language it is hoped that HTML5 will improve interoperability: so that web developers can develop content that conforms to the majority of hardware devices and software applications. Due to the popularity of browsing the World Wide Web using mobile devices, having a single markup language that can create content that is compatible with traditional technology and mobile devices is highly desirable.
HTML5 includes a range of new elements - that primarily provide support for multimedia content - and some new attributes; a selection of visual HTML elements have been removed. Due to HTML5's support for multimedia content, it is generally accepted that the Adobe Flash plugin is no longer required for viewing video content in a browser; in 2011, Adobe discontinued the development of Flash. The syntax of HTML5 is based upon XML, and not SGML.
The first markup language designed for the World Wide Web was HTML; released in 1991. HTML has been released in a variety of versions; the last standardised version was HTML 4.0: released in December, 1997. Due to the rigid structure of HTML - it is not suited to large data structures - the World Wide Web Consortium (W3C) decided to create a new markup language that would be more powerful and adaptable than HTML: this markup language as XML and was released in 1998.
Due to it's complexity, XML never became as popular as HTML. In 1998, the World Wide Web Consortium (W3C) released XHTML: a combination of XML and HTML, a compromise that they hoped would enable developers to start using a XML inspired markup language. However, the Web Hypertext Application Technology Working Group (WHATWG) - a group comprised of web browser developers - were disappointed by the lack of a new standardised HTML version.
The WHATWG group was formed in 2004, and it's goal was to develop a new version of HTML; at this point in time, the W3C was primarily focused upon developing XHTML. By 2007, the W3C agreed to jointly develop HTML5; it had previously voted against developing HTML. In 2008, a working draft of HTML5 was produced, and by 2011, HTML5 had advanced to such a degree that the development of XHTML was halted. HTML5 was released in 2014, and is maintained by WHATWG and W3C.