In March 1989, Sir Tim Berners-Lee, while working at CERN, wrote a proposal to develop a distributed information system. He resubmitted a slightly edited version in May 1990.

In November 1990, Sir Tim Berners-Lee, together with CERN colleague, Robert Cailliau, submitted a formal management proposal for ‘WorldWideWeb: Proposal for a HyperText Project’. 

By Christmas 1990, Sir Berners-Lee had defined the Web’s basic concepts, the html, http and URL, and he had written the first browser/editor and server software. info.cern.ch was the address of the world's first web server, running on a NeXT computer at CERN. The world's first web page address provided information about the World Wide Web project.

By March 1991, a simple ‘Line-Mode’ browser was made available to users of CERN’s central computers. Although it had less features than the more sophisticated NeXT browser/editor, it had the big advantage of being able to run on a wider range of computers. It was written by Nicola Pellow during her student work placement at CERN. A project to restore the first ever Website includes a description of the Line Mode browser.  

In August 1991, Sir Berners-Lee announced his WWW software on Internet newsgroups and interest in the project spread beyond the physics community. The first announcement was on 6 August 1991 to alt.hypertext, a newsgroup for hypertext enthusiasts. He described the project and provided instructions for obtaining the WWW software from CERN.

On 12 December 1991, the first web server outside Europe was installed at the Stanford Linear Accelerator Center (SLAC)in California. It provided access to SPIRES, a database with information for scientists working in HEP (High Energy Physics), including the ability to search for publications.

By January 1992, the WWW software at CERN had matured from an early prototype to a useful and reliable service. Through CERN’s Computer Newsletter, thousands of scientists learnt how they could use the web to access a useful set of information, e.g. phone numbers, email addresses, news groups, as well as computing and software documentation.

By late 1992, the WWW project had a growing list of early web servers. They were mainly located at academic sites collaborating with CERN but interest was starting to spread beyond academia. Development was also progressing on early graphical browsers (e.g.  MIDAS by Tony Johnson from SLAC, Viola by Pei Wei from technical publisher O'Reilly Books, and Erwise by Finnish students from Helsinki University of Technology).

From January 1993, the National Center for Supercomputing Applications (NCSA) at the University of Illinois, provided pre-releases of its Mosaic browserfor the Unix X Window System. The first official release was on 21 April 1993. Mosaic quickly gained popularity, becoming the browser of choice, with its user-friendly graphical interface and easy installation. Versions of Mosaic running on PC and Mac became available later that year.

On 30 April 1993, CERN issued a statement putting the Web into the public domain, ensuring that it would act as an open standard. The move had an immediate effect on the spread of the web. Further licensing actionswere taken to allow the Web to evolve and flourish. By late 1993 there were over 500 known web servers, and the WWW accounted for 1% of Internet traffic. 

In May 1994, Robert Cailliau organized the world’s First International World-Wide Web Conference at CERN. It was attended by 380 users and developers, and was hailed as the “Woodstock of the Web”.

In October 1994, Sir Tim Berners-Lee founded the World Wide Web Consortium (W3C) - at the Massachusetts Institute of Technology laboratory for computer science - in collaboration with CERN and with support from DARPA and the European Commission. Sir Berners-Lee moved to the Massachusetts Institute of Technology (MIT), from where he remains Director of the World Wide Web Consortium (W3C). 

By the end of 1994, the Web had 10,000 servers - of which 2000 were commercial - and 10 million users. Traffic was equivalent to shipping the collected works of Shakespeare every second.

In March 2019, it will be 30 years since Sir Tim Berners-Lee submitted his proposal for what would become the World Wide Web. To mark this occasion, CERN will hold an event to celebrate the Web@30. For the 29^thanniversary, in March 2018, Sir Tim Berners-Lee published a letter to the world about issues facing the web today: https://webfoundation.org/2018/03/web-birthday-29/.