Two of the key concepts in object-oriented programming (OOP) ... We’ll use this project to work with the examples of inheritance and ... composition allows for greater flexibility and modularity.

In OOP, you achieve modularity by taking advantage of classes. In AOP, you achieve modularity by taking advantage of aspects. An aspect might be logging or authentication, for example.

Proponents of object-oriented techniques point to the flexibility and extensibility of object-oriented systems along with other benefits such as increased modularity, abstraction, and encapsulation.

Baldwin, Carliss Y., and Kim Clark. "The Option Value of Modularity in Design An Example from Design Rules, Volume 1: The Power of Modularity." Harvard Business School Working Paper, No. 02-078, May ...