to general net theory.- Elements of general net theory.- Formal properties of place/transition nets.- Linear algebra in net theory.- Atomicity of activities.- Concurrency.- The relative strength of K-density.- Reductions of nets and parallel programs.- Adequacy of path programs.- Performance evaluation of systems using nets.- Survey of French research and applications based on Petri nets.- Nets in modeling and simulation.- Abstractions of net models.- Applications of net-based models.- The application of general net theory — A personal history.- Petri-nets from the engineer's viewpoint lecture I.- Nets as a tool in teaching and in terminology work.- Structured representation of knowledge by Petri nets as an aid for teaching and research.- A dictionary of some basic notions of net theory.- Addresses of all authors.