Composite structure diagrams are used to visualize the internal structure of a system, including the relationships between its components. They are used to represent the hierarchical relationships between components, as well as the relationships between components and their environment. Composite structure diagrams are useful for understanding the overall structure of a
From Wikipedia
Composite structure diagram in the Unified Modeling Language (UML) is a type of static structure diagram that shows the internal structure of a class and the collaborations that this structure makes possible.