In sequence diagrams, partitions in activity diagrams, and regions in state machine diagrams, by default, any changes that you make to the model are reflected in the diagrams that represent the model. Conversely, any changes that you make to the diagram are reflected in the model. You can set the canonical property to false so that changes in the model are not synchronized with the diagram.
Parent topic: Graphically representing models by using modeling diagrams
Related concepts
Types of modeling diagrams