The World Wide Web Consortium (W3C) develops international standards for the Web: HTML, CSS, and many more.
The W3C is an international community where Member organizations, a full-time staff, and the public work together to develop Web standards. Led by Web inventor and Director Tim Berners-Lee and CEO Jeffrey Jaffe, W3C’s mission is to lead the Web to its full potential.
The W3C Web Accessibility Initiative (WAI) develops standards and support materials to help understand and implement accessibility to make websites, applications, and other digital creations more accessible and usable to everyone. — from W3C website