HTML5 is the latest version of HTML. Several new tags were added in html5 like header, footer, article and aside etc..
HTML 5 is the next major version of the HTML standard HTML 4.01, XHTML 1.0 and XHTML 1.1. HTML 5 is a standard for structuring and presenting content on the World Wide Web. HTML 5 is cooperation between the World Wide Web Consortium and the Web Hypertext Application Technology Working Group (WHATWG). HTML 5 introduces a number of new elements and attributes that helps in building a modern websites.
HTML 5 users need to use simple syntax to specify Doctype. More over HTML 5 authors can use simple syntax to specify character encoding. In HTML 5 following tags have been introduced for better structure. Section: this tag represents a generic document or application section. Article: this tag represents an independent piece of content of a document such as a blog entry on newspaper article. Header: this tag represents the header of a section. Footer: this tag represents the footer of a section. Nav: this tag represents a section of the document intended for navigation. Dialog: this tag can be used to mark up a conversation. Figure: this tag can be used to associate a caption together with some embedded content, such as graphic or video. HTML 5 SVG: SVG stands for Scalable Vector Graphics. SVG is a language for describing 2D graphics and graphical applications in XML and XML is then rendered by an SVG viewer. SVG is mostly useful for vector type diagram like Pie charts, two dimensional graphs in X, Y coordinate system. Embedding SVG in HTML 5: HTML 5 allows embedding SVG directly using SVG tag
ARIA is a standard developed at World Wide Web in response to the generally poor accessibility of early AJAX based web applications. Using HTML 5 one can cut down on the amount of mark up required to provide an accessible user experience. Custom date attributes allow user to add arbitrary data to elements for their own purpose. Microdata extend the expressive power of HTML to cover things that are not strictly mark up. One can use Microdata to designate a portion of the page as describing contact information, a calendar event or licensing information.