- Choreography defines the sequence and conditions under which multiple cooperating independent agents exchange messages in order to perform a task to achieve a goal state.
- Service represents a capability of performing tasks that represents a coherent functionality.
- A service role is an intermediate abstraction between service and task. A given message that is received by a service may involve processing associated with several service roles.
- A service task is an abstraction that encapsulates some intended effect of invoking a service.