Exit refers to the act of exiting a previously entered state during the execution of a state machine. A state may declare exit actions, which will be executed when a state is exited.
If a state is a compound or parallel state, any substates are also exited.
The exit of a state is defined to be instantaneous for all practical purposes; this includes the execution of any exit actions, and the exit of all substates.
There is no notation associated with the actual exit of a state, since it happens during a statechart’s execution.