Web browser

Tim Berners-Lee didn't just invent the World Wide Web in 1989—he invented the first application to navigate it. His WorldWideWeb (later renamed Nexus) was both browser and editor, reflecting his vision of the web as a collaborative workspace rather than a broadcast medium. Running on NeXT computers at CERN in 1990, the program could retrieve documents via HTTP, render HTML with styled text, and follow hyperlinks. But NeXT machines were expensive and rare. The web remained a CERN curiosity until browsers could run on commodity hardware.

The adjacent possible was ready. Graphical user interfaces had matured through the Mac and Windows. The internet backbone existed. Hypertext concepts were well-established—Apple's HyperCard had popularized clickable links since 1987. What was missing was a bridge: software that could translate the web's technical protocols into intuitive visual navigation that non-programmers could use.

The Line Mode Browser, also from CERN, worked on any terminal but was text-only. Viola and Erwise experimented with graphics on Unix. Then Mosaic arrived. Marc Andreessen and Eric Bina at the National Center for Supercomputing Applications released Mosaic in January 1993, and it spread like wildfire through university networks. Mosaic rendered images inline with text—revolutionary for scientists who wanted to share diagrams. It was fast, free, and available for Unix, Mac, and Windows. By October 1994, over 3 million users were browsing the web.

Mosaic's success spawned Netscape, founded by Andreessen in 1994. Netscape Navigator dominated the market until Microsoft bundled Internet Explorer with Windows 95, triggering the browser wars that would shape the internet's commercial era. Each iteration expanded what browsers could do: JavaScript for interactivity (1995), CSS for styling (1996), AJAX for seamless updates (2005), HTML5 for multimedia (2014). The browser transformed from document viewer into application platform.

The cascade was profound. Browsers enabled e-commerce (Amazon, eBay), search engines (Yahoo, Google), social networks (Friendster, Facebook), and eventually cloud applications that replaced desktop software. The browser became the universal client—a standardized window through which users accessed an ever-expanding universe of services. Chrome's 2008 launch brought the V8 JavaScript engine, making browsers fast enough to run sophisticated applications. By 2025, browsers had evolved into operating systems within operating systems, with Web Assembly enabling near-native performance. The humble document viewer had become the primary interface through which humanity accessed digital services.