Actor (1/3)
Actors interact with the system …
by using use cases,
i.e., the actors initiate the execution of use cases.
by being used by use cases,
i.e., the actors provide functionality for the execution of use cases.
Actors represent roles that users adopt.
Specific users can adopt and set aside multiple roles simultaneously.
Actors are not part of the system, i.e., they are outside of the system
boundaries.
Alternative notations: