The UML Class diagram is used to visually describe the problem domain in terms of types of object (classes) associated with each other in different ways. UML Class Diagram View more presentations from Eran Toch . Association The most abstract way to describe static relationship between classes is using the ‘Association’ link, which simply states that there is some kind of a link or a dependency between two classes or more. Weak Association ClassA may be linked to ClassB in order to show that one of it methods includes parameter of ClassB instance, or returns instance of ClassB. Strong Association ClassA may also be linked to ClassB in order to show that it holds reference to ClassB instance. Aggregation (Shared Association) In cases where there’s a part-of relationship between ClassA (whole) and ClassB (part), we can be more specific and use the aggregation link instead of the association link, taking special notice that ClassB can also be aggregated by other classes in the ap...