From each state comes a complete set of transitions that determine the subsequent state. States are rounded rectangles. Transitions are arrows from one state to another. Events or conditions that trigger transitions are written beside the arrows. Our diagram has two self-transition, one on Getting SSN and another on Getting PIN .
Final states are also dummy states that terminate the action.
While in its Validating state, the object does not wait for an outside event to trigger a transition. Instead, it performs an activity. The result of that activity determines its subsequent state. An activity diagram is essentially a fancy flowchart. Activity diagrams and statechart diagrams are related.