When Tim Berners-Lee sketched out what we now know as the World Wide Web, he offered it as a solution to an age-old but prosaic source of problems: documentation. In 1989 the computer scientist was working at CERN, the particle physics laboratory near Geneva, just as a major project, the Large Electron Positron collider, was coming online. CERN was one of the largest Internet sites in Europe at the time, home to thousands of scientists using a variety of computer systems. Information was stored hierarchically: a treelike central repository held documents at the end of its branches. Finding a file meant crawling up the trunk and out to the right leaf. Scientists who were new to CERN (and there were a lot of them—most researchers stayed only for brief, two-year stints) had a hard time figuring out which branches to venture onto to find the right information for their project.

In a proposal to CERN management that March, Berners-Lee suggested constructing a system that operated more like the working structure of the organization itself: “A multiply connected ‘web’ whose interconnections evolve with time,” he wrote in Information Management: A Proposal. Information would no longer be stored on hierarchal trees; instead a forest of nodes would be connected by links. “When describing a complex system,” he wrote, “many people resort to diagrams with circles and arrows.... The system we need is like a diagram of circles and arrows, where circles and arrows can stand for anything.”

It was this agnosticism regarding content that gave what became the Web the power it has today. The system Berners-Lee finished on Christmas Day in 1990 was imbued with flexibility at every level: any file could be identified by its unique address, or Universal Resource Locator (URL). Behind the scenes, the Hypertext Transfer Protocol (HTTP) provided a uniform language for different types of computer systems to communicate with one another. And simple Hypertext Markup Language (HTML) linked documents together and specified how they should appear. Equally important, the components were made available free of charge to anyone who wanted them. Two decades later the World Wide Web has proven itself to be the most effective information dissemination platform ever created.