Working at CERN, the European particle physics laboratory, Tim Berners-Lee circulated a proposal to his supervisor outlining a system of linked hypertext documents to help researchers share information across incompatible computers. His supervisor, Mike Sendall, famously scrawled "vague but exciting" on the cover. Within three years, Berners-Lee's idea had grown into the World Wide Web.
CERN in the late 1980s was a mess of incompatible computer systems, thousands of researchers from dozens of countries using different machines, operating systems, and document formats, unable to easily share data with each other. Tim Berners-Lee, a British software engineer working there, wrote a proposal titled "Information Management: A Proposal," describing a way to link documents together using hypertext so anyone could jump between related pieces of information regardless of what computer stored them.
His supervisor Mike Sendall read it and wrote across the top: "Vague but exciting." It was not immediately approved as a formal project, but Sendall allowed Berners-Lee to pursue it quietly on the side, giving him a NeXT computer to develop it on.
By late 1990, Berners-Lee had built the first web browser, the first web server, and the first webpage, describing the very project that created them. He released the software freely, without patent or royalty, a decision that let it spread virally across universities and eventually the entire planet. The document that started it all still survives, its terse annotation now one of the most famous margin notes in technological history.
Key people: Tim Berners-Lee, Mike Sendall