UML Collaboration Diagrams
A major task of the design phase is creating the interaction diagrams for the system operations. Read this section to learn more about collaboration diagrams. As you review the examples, consider general principles in assigning responsibilities. Ask yourself, how do you determine the relationship between objects? How can you extract the classes? How do you determine whether a mentioned feature can be considered a class attribute? How would you determine class methods?
Conclusion
Collaboration diagrams are mainly used during the object-oriented design phase. They are flexible to add new concepts in two dimensions, hence occupy less space. In design phase, objects are supposed to be provided with operations to perform. Collaborations are easily used for this purpose with the help of a Pattern which facilitates assigning responsibility to objects.