[stebann]

They can be used for modelling actions and states, including the tricky cases where an automaton would become too complex.

[kitd]

Indeed. Finite state machines are a subset of Petri nets, having deterministic state transitions. Petri nets are useful where concurrent state transitions needs to be modelled, and are thus useful when modelling the physical world.

[stebann]

Thanks. I forgot to appoint that.