Class Relationship

1. Aggregation - "part of" relationship

- Composition is form of aggregation.

- Composition relationship is static. A is composed of B. B can not exist on its own. [Engine in a car]

- Aggregation relationship is dynamic. A aggregates B. A and B can exist on their own. [Airplanes at an airport]

2. Generalization / Specialization - "is-a"

- Inheritance

3. Association