More useful information from Nicolas Le Novere! He had written:
> SBGN Process Descriptions are representations of ... processes, as used in chemical kinetics (and in general in general systems theory). One can derive an ODE system from an SBGN PD (the opposite is harder). SBGN Entity relationships correspond to rule-based models (e.g. models encoded in BioNetGen, Kappa etc.). SBGN Activity Flows correspond to logical models (the approaches used by Stuart Kauffman and Rene Thomas).
> Thanks, you don't know how helpful that is to me! I'm familiar with getting systems of ODE in chemistry from "chemical reaction networks", so I'm hoping "process descriptions" are similar but more general. The others are less familiar to me but I'll learn about them.
> Absolutely. The Process Description language was the first SBGN language, and evolved from the "CellDesigner notation". CellDesigner is a software that was originally a graphical editor for a modelling language called SBML (the initial name of the software was SBedit). And SBML was essentially based on list of reactions. (Nowadays, it is way more, but that was the initial aim.)
> As for the others, the Entity Relationship language evolved from the Molecular Interaction Maps of Kurt Kohn:
> The Activity Flows are just what molecular biologists use on their powerpoint presentations really.
> A fairly long presentation on SBGN can be found here: