Computer Novel Construction Set a.k.a. CNCS, created by Hayden Software. An obscure and arguably the first text adventure creation program for the IBM PC. Released in 1985 it is a fore runner to today's point and click authoring systems, using a series of DOS based menus and pop-up windows to create your world and all the objects and characters that populate it. CNCS gives you the power to create games much more advanced than any of the games released by Hayden Software themselves at that time.
The Computer Novel Construction Set enjoyed a short lived revival between 2001 and 2002 as some episodes in the long running Adventure Game Studio series Reality on the Norm were written in this format, breaking away from the series point and click adventure roots.
The many games written in this format have all but disappeared, the ones that remain are just as obscure as their engine. Of the few still in existence the most notable are Virgin Schoolgirl, the interactive fiction episodes of Reality-On-The-Norm and the Oz Game Collection, a series of remakes of US Gold text adventures originally written for the Commodore 64 and ported to the PC by Dorothy and Ozma Productions.