There is a main attribute called Process Type which has two options - Private and Public. What is the significance of this attribute?
Generally you could say - a process with message flow is public - without one is private.
Private Business Processes are those internal to a specific organization. These Processes have been generally called workflow or BPM Processes. Another synonym typically used in the Web services area is the Orchestration of services. There are two types of private Processes: executable and non-executable.
A public Process represents the interactions between a private Business Process and another Process or Participant. Only those Activities that are used to communicate to the other Participant(s) are included in the public Process.
For further information please consult the BPMN specification: https://www.omg.org/spec/BPMN/2.0/PDF/
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