Tim Berners-Lee created HTML in the early 1990s at CERN to share data between physicists. It was the underpinning language of the newly created World Wide Web. The first HTML specification was released in 1991 with 18 tags. Over the 1990s, HTML evolved through versions 1, 2, 3.2, and 4 to support more multimedia and interactivity. XHTML was created in 2000 as a reformulation of HTML using XML. HTML5 was started in 2006 to update HTML for modern web applications while maintaining backward compatibility.