Here is a historical overview of the development of HTML (Hypertext Markup Language), particularly leading up to the creation of HTML5.
- Early HTML Development: HTML was initially developed at CERN and then at the IETF (Internet Engineering Task Force) during its first five years from 1990 to 1995. It went through revisions and extensions during this period.
- Formation of W3C: With the establishment of the World Wide Web Consortium (W3C), the development of HTML shifted to this organization. HTML 3.0 was an early attempt, but it was replaced by HTML 3.2 in 1997. HTML4 followed later in the same year.
- Transition to XHTML: In 1998, the W3C decided to stop evolving HTML and began working on an XML-based equivalent called XHTML. XHTML 1.0 was completed in 2000, which was a reformulation of HTML4 in XML.
- XHTML Modularization: After XHTML 1.0, the W3C focused on making it easier for other working groups to extend XHTML, which was done under the banner of XHTML Modularization.
- XHTML2 and DOM Levels: In parallel with these efforts, the W3C also worked on XHTML2, a new language not compatible with earlier HTML and XHTML. Meanwhile, parts of the API for HTML developed by browser vendors were specified in DOM (Document Object Model) levels 1, 2, and 3, although some of these efforts didn't reach completion.
- Renewed Interest in HTML: In 2003, the publication of XForms sparked renewed interest in evolving HTML itself rather than seeking replacements for it. Some efforts were made to extend HTML4's forms to include features similar to those introduced in XForms.
- Formation of WHATWG: The idea to reopen HTML's evolution was tested at a W3C workshop in 2004 but was initially rejected. Subsequently, Apple, Mozilla, and Opera jointly announced their intent to work on HTML under a new venue called the WHATWG (Web Hypertext Application Technology Working Group). This group emphasized the importance of backward compatibility, matching specifications and implementations, and detailed specifications to ensure interoperability.
- Collaboration between W3C and WHATWG: In 2006, the W3C expressed interest in participating in the development of HTML5. A working group was formed in 2007 to collaborate with the WHATWG on HTML5 development. This collaboration allowed the W3C to publish the specification under its copyright while maintaining a version on the WHATWG site.
- Divergence in Goals: In 2011, it became apparent that the W3C and WHATWG had different goals. The W3C aimed to publish a "finished" version of HTML5, while the WHATWG wanted to maintain a living standard for HTML, continuously updating it as needed and addressing known problems.
- Collaboration Agreement: In 2019, the WHATWG and W3C signed an agreement to collaborate on a single version of HTML, leading to the creation of a unified HTML specification.
This history provides context for the development of HTML5 and the collaboration between different organizations and individuals to shape the evolution of HTML into the modern web technology we use today.
