The legendary Goldratt Simulator (GSim) was built by Eli Schragenheim in 1986 on the base of the computerized OPT game that he developed in 1984.
The basics of the Theory of Constraints (TOC) methodology was described in “The Goal”. Simulator show idea of drum-buffer-rope (DBR and S-DBR) principles.
It gives an idea to define bottleneck a properly working with constraints through buffer management in MTO (make to order) production