World Wide Web

The internet existed for two decades before Tim Berners-Lee invented the World Wide Web. Email worked. File transfer worked. But the network was fragmented—each system required specialized knowledge, different protocols, specific clients. There was no universal way to link information across institutions, no simple method for non-technical users to publish and navigate connected documents. Berners-Lee, working at CERN, faced a practical problem: physicists from around the world needed to share documentation, but the lab's computing ecosystem was a chaos of incompatible systems.

In March 1989, Berners-Lee proposed 'a large hypertext database with typed links.' The memo met indifference—his supervisor famously scribbled 'Vague but exciting' on it. Undeterred, Berners-Lee built the system himself over the next two years. The key innovation was combining three existing ideas into something new: hypertext (clickable links between documents, theorized since Vannevar Bush's 1945 Memex), the internet (the physical network), and unique resource identifiers (addresses for every document). HTML gave documents structure; HTTP defined how servers and clients communicated; URLs provided addresses. Together, these formed the Web.

The adjacent possible was precisely configured by 1989. The internet infrastructure existed. Hypertext concepts had been refined through systems like Apple's HyperCard. NeXT computers at CERN provided development tools. Perhaps most crucially, CERN's culture of open collaboration meant Berners-Lee could release his work freely—in 1993, CERN officially placed the Web technology in the public domain, ensuring no single entity could own the protocols.

The cascade was unlike anything in technological history. Mosaic browser (1993) made the Web visual. Netscape and Internet Explorer brought it to consumers. Amazon, eBay, and Yahoo demonstrated commercial potential. Google organized the chaos. Facebook and YouTube transformed media. Each wave built on the open foundations Berners-Lee had established. Unlike videotex systems that preceded it, the Web was decentralized—anyone could publish, anyone could link, no gatekeeper controlled access.

By 2025, the Web had become humanity's primary information infrastructure. Over 5 billion people accessed it regularly. The original vision—a collaborative hypertext system for physicists—had evolved into the substrate for commerce, communication, entertainment, and knowledge. Berners-Lee's decision to keep it open rather than proprietary proved pivotal: the Web's architecture enabled innovation at the edges, allowing successive generations of creators to build upon what came before.