HTML5 is a markup language used for structuring and presenting content on the World Wide Web.
It is the fifth and final major HTML version that is a World Wide Web Consortium (W3C) recommendation.
HTML5 was first released in a public-facing form on 22 January 2008,with a major update and "W3C Recommendation" status in October 2014.
Its goals were to improve the language with support for the latest multimedia and other new features; to keep the language both easily readable by humans and consistently understood by computers and devices such as web browsers, parsers, etc.,
HTML5 introduces elements and attributes that reflect typical usage on modern websites.
HTML5 is designed so that old browsers can safely ignore new HTML5 constructs.
Official website :- https://html.spec.whatwg.org/