Every computer scientist studies Petri nets in their early academic years. Petri nets are a powerful yet very intuitive modeling tool for concurrent and distributed systems. Such networks were introduced by Carl Adam Petri (1926-2010) in his PhD thesis, in 1962, and from that date forward studied all over the world and still widely applied today. But who was Carl Adam Petri? How did he interact with the scientific community and engage his students?

This book is a tribute to him and his work, made by international scientists that either met him in workshops and symposiums or worked directly with him. It contains several personal tributes and anecdotes, for example, how Petri prepared slides or how he was fascinated by other areas, such as physics and biology.

The book is divided into four parts. The first part relates to Petri nets and how they are used, disseminated, and discussed. The second part is a more intimate set of anecdotes on how fellow scientists worked and interacted with him, with very different points of view. The third part covers technical and research themes, such as timed Petri nets (TPNs), process algebras, and how Petri nets continue to evolve. The concluding fourth part is on how those nets are used outside computer science, for example, in disciplines such as biology or circuits.

The book is a tribute to Carl Adam Petri, both as a human being and a scientist. In particular, it is an important look at how Petri nets have developed over the years in the scientific community. The book is suggested reading for both undergraduate and doctoral students in many disciplines, from computer science to physics and biology, to further investigate possible applications of nets in their field. Prior knowledge of Petri nets is highly recommended.