First web server

By late 1990, Tim Berners-Lee had secured the collaboration of Belgian systems engineer Robert Cailliau, who helped refine the project description and advocate for resources within CERN. Working on a NeXTcube computer provided by his manager, Berners-Lee set out to build a fully functional prototype of the distributed hypertext system proposed eighteen months earlier. Over the autumn of 1990, he authored the core protocols and software components that would define the Web.

Berners-Lee invented three primary technologies during this intense development period: HyperText Markup Language (HTML) to format documents, Hypertext Transfer Protocol (HTTP) to exchange data between computers, and Universal Resource Identifiers (URIs, later URLs) to assign a unique global address to every web page. He wrote the software for the first web server software (known as `cern_httpd`) and built the first browser and authoring application, which he named "WorldWideWeb".

By December 25, 1990, the entire software stack was operational on the NeXTcube workstation in CERN Building 31. The server went live on the internal CERN network, accessible at the address `info.cern.ch`. That Christmas Day marked the first time hypertext documents were successfully retrieved over an IP network from a dedicated web server by a browser application running on a separate machine. To ensure the server remained operational, Berners-Lee attached a prominent label written in red ink directly to the computer casing warning colleagues not to turn off the power.

The deployment of the first web server provided tangible proof-of-concept for a global information network. Soon after, mathematics student Nicola Pellow joined the team to write a simple line-mode browser that could run on standard computer terminals, ensuring that researchers lacking expensive NeXT hardware could still access the emerging web database.