Berners-Lee proposes the World Wide Web at CERN
A physicist's memo to solve CERN's own information mess becomes the basis for the web
Quick facts
- Inventor
- Tim Berners-Lee, CERN
- Collaborator
- Robert Cailliau (formal proposal, November 1990)
- Initial proposal
- 12 March 1989
- Public software release
- 1991
What happened
Tim Berners-Lee, a software engineer at CERN, the European particle physics laboratory, wrote a proposal in March 1989 for what he called an information management system, meant to solve the practical problem of CERN's own scattered documentation, spread across incompatible formats and systems used by scientists visiting from around the world. Working with Belgian colleague Robert Cailliau, he formalized the idea as a management proposal in November 1990 and, by Christmas 1990, had defined the core pieces still used today, HTML for formatting documents, HTTP for transferring them, and the URL for addressing them, and had written the first web browser and server software himself. In 1991, he released the software, first to CERN colleagues and then, that August, to internet newsgroups worldwide.
Why it matters
Berners-Lee designed the web to run on top of the internet that already existed rather than building a new network, meaning anyone already connected to the internet could use it once they had the software, which is a large part of why it spread so quickly once released.
How we know
CERN's own history of the web documents the March 1989 proposal, the November 1990 formal proposal with Cailliau, and the 1991 software release directly from the institution where it happened.
Sources
- CERN. A short history of the Web · Primary source (author-declared)home.cern · Cited as a "primary" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
- Tim Berners-Lee, hosted by W3C (World Wide Web Consortium). The original proposal of the WWW, HTMLized · Primary source (author-declared)w3.org · Cited as a "primary" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
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