What is an actor?

What is an actor?

• A. A person
• B. An external system
• C. A person or external system that interfaces with your system
• D. A data structure

Answer: (C)

In system modeling, an actor is any external entity that interacts with the system to achieve a goal. It isn’t limited to people; it can be a person or another system or external service that communicates with your system through inputs or messages. This is why the best answer is the one that says a person or external system that interfaces with your system. The other ideas are too narrow: a person is only part of what an actor can be, and an external system is only part of what an actor can be. A data structure is an internal component, not an external entity that interfaces with the system.

In system modeling, an actor is any external entity that interacts with the system to achieve a goal. It isn’t limited to people; it can be a person or another system or external service that communicates with your system through inputs or messages. This is why the best answer is the one that says a person or external system that interfaces with your system.

The other ideas are too narrow: a person is only part of what an actor can be, and an external system is only part of what an actor can be. A data structure is an internal component, not an external entity that interfaces with the system.