Everything You Always Wanted to Know About Petri Nets, but Were Afraid to Ask
Business Process Management (BPM), Process Mining (PM), Workflow Management (WFM), and other approaches aimed at improving processes depend on process models. Business Process Model and Notation (BPMN), Event-driven Process Chains (EPCs), and UML activity diagrams all build on Petri nets and have semantics involving 'playing the token game'. In addition, process analysis approaches ranging from verification and simulation to process discovery and compliance checking often depend on Petri net theory. For the casual user, there is no need to understand the underlying foundations. However, BPM/PM/WFM researchers and 'process experts' working in industry need to understand these foundational results. Unfortunately, the results of 50 years of Petri net research are not easy to digest. This tutorial paper provides, therefore, an entry point into the wonderful world of Petri nets.