Graph grammars are a powerful model of concurrent and distributed systems which can be seen as a proper extension of Petri nets. Inspired by this correspondence, a truly concurrent semantics has been developed along the years for the algebraic approaches to graph grammars, based on Winskel’s style unfolding constructions as well as on suitable notions of processes. A basic role is played in this framework by the study of contextual and inhibitor nets, two extensions of ordinary nets which can be seen as intermediate models between ordinary Petri nets and algebraic graph grammars.
This paper presents a survey of these results, discussing in a precise, even if informal way, some of the main technical contributions that made possible the development of such a theory