Class Diagrams: Composition and Aggregation

Composition is a special type of aggregation that denotes a strong ownership of the Class "All" to Class "Party". Is plotted with a diamond diamond padding against the class that represents the whole. Aggregation is a relationship in which the Class "All" plays a more important role than the Class "Party", but the two classes are not dependent on each other. Is plotted with a diamond diamond vacuum against Class "All".