Shallow history (shallowHistory) represents a return to only the topmost substate of the most recent state configuration, which is entered using the default entry rule. Source Unified Modeling Language 2.5.1
If there is no outgoing Transition inside the composite State, then the incoming Transition simply performs a default State entry. Source Unified Modeling Language 2.5.1
If the Transition explicitly enters one or more Regions (in case of a fork), these Regions are entered explicitly and the others by default. Source Unified Modeling Language 2.5.1
If the Transition terminates on the edge of the composite State (i.e., without entering the State), then all the Regions are entered using the default entry rule above. Source Unified Modeling Language 2.5.1
Composite state entry and exit points Gallery Tutorial TRAIL: Webel's ultimate guide to Systems Modeling Language (v1) with MagicDraw/Cameo Section 01:03: UML Behavior: StateMachines quick start Slide kind UML StateMachine Diagram
