I believe IBM Generalized Markup Language evolved into SGML (Standard Generalized Markup Language) which was used heavily at CERN when Tim Berners-Lee was worki

I believe IBM Generalized Markup Language evolved into SGML (Standard Generalized Markup Language) which was used heavily at CERN when Tim Berners-Lee was working on HTML, which is heavily derived from it. I find this interesting about HTML: some form of the markup language had been floating around for decades until Berners-Lee added hyperlinks to it.