AFAIK, browser companies and various other individuals who were unhappy with the W3C being slow and out of touch with real-world browser development and usage d

AFAIK, browser companies and various other individuals who were unhappy with the W3C being slow and out of touch with real-world browser development and usage decided to split off and maintain their own version of the HTML5 standard - this WHATWG version is the one that the industry considers canonical (I'm not too sure on the actual differences between specs; it's been a while since I did any work where modern technology was an option, so my info mostly comes from tech news sites...)