Well... Right here on the the very first website Tim Berners-Lee talks about how to build interactive web applications (here called "gateways"), albeit server-s

Well... Right here on the the very first website Tim Berners-Lee talks about how to build interactive web applications (here called "gateways"), albeit server-side rather than client-side: https://info.cern.ch/hypertext/WWW/FAQ/Server.html https://info.cern.ch/hypertext/WWW/FAQ/Server.html