October 3rd, 2017
The Web Platform Working Group has published a W3C Recommendation of HTML 5.1 2nd Edition. This specification defines the 2nd edition of the 5th major version, first minor revision of the core language of the World Wide Web: the Hypertext Markup Language (HTML). In this version, a significant error with HTML 5.1 has been rectified, as noted in the Errata corrected section. Meanwhile, new features continue to be introduced to help Web application authors, new elements continue to be introduced based on research into prevailing authoring practices, and special attention continues to be given to defining clear conformance criteria for user agents in an effort to improve interoperability in the development of HTML 5.2.