The Plan and BPMN-based processes use a similar set of modeling element in their workflows with some additional modeling element available for the BPMN-based process workflows so that you can model logic that is accommodated by Goal hierarchies:
A Plan Model is a sum of all elements with execution semantics encapsulated in a Plan.
Every Plan Model:
Apart form that, it can contain an arbitrary number of activities, events, flows, and gateways connected with Sequence Flows (Connectors). The elements in the flows must meet their modeling rules and must create an uninterrupted workflow.
A Plan Model is triggered when the parent Plan becomes Running and its None Start Event produces a token and the respective namespace context is initiated.
A BPMN Process Model is a sum of all elements with execution semantics encapsulated within a BPMN-based Process.
A BPMN-based Process:
Apart form that, it can contain an arbitrary number of activities, events, and gateways connected with sequence flows. The elements in the flows must create an uninterrupted workflow and meet any other modeling rules that apply.
When a Process with a None Start Event is instantiated:
When a Process with another type of Start Event is instantiated:
Note: If a BPMN-based Process instance ends with an uncaught Error End Event, the last transaction is rolled back.