Abstract
The definition of process admitted here follows the line developed for elementary (1-safe) Petri nets and published in [Cza 99], [Cza 2000a], [Cza-Kud 2000]. It pertains not to any particular net, thus allows for collecting processes into arbitrary sets, i.e. process languages, and for asking questions like: for a given process language decide if there exists a Place/Transition net and if yes, contruct it (synthesis). The collection of all process languages is a semantic domain for Place/Transition nets. ω-process languages contain both finite and infinite processes. The main problems pursued are analysis, synthesis and iteration lemmata for ω-process languages. Surprisingly, the problems enjoy much simpler solutions for processes generated by P/T nets than generated by elementary nets.