The Web Hypertext Application Technology Working Group, known as WHATWG, is a community that develops standards for the web. According to its own FAQ, it is “a community of people interested in evolving the web through standards and tests.”
WHATWG was established in 2004 by Apple, Mozilla, and Opera following a W3C workshop. The FAQ explains that the founders were dissatisfied with the W3C’s direction at the time, citing the W3C’s focus on XHTML, its “lack of interest in HTML,” and an “apparent disregard for the needs of real-world web developers.” Rather than continue down the XHTML path, the group set out to extend HTML for building web applications.
The work WHATWG started became HTML5 and, more broadly, a new way of maintaining web standards. Instead of publishing frozen, versioned documents, WHATWG treats its specifications as Living Standards that are continuously updated. The FAQ describes adding new features “at a rate intended to keep the standard a little ahead of the implementations,” keeping the written standard aligned with what browsers actually support.
In 2017, Apple, Google, Microsoft, and Mozilla formalized the organization with an intellectual-property policy and a Steering Group. Today WHATWG maintains the HTML Standard and related specifications that define the core of how the web works.