• Data and Operations

• Interface and Implementation

• The Messaging Metaphor

• Classes

• Modularity

• Reusability

• Mechanisms Of Abstraction

• Encapsulation

• Polymorphism

• Inheritance

• Class Hierarchies

• Subclass Definitions

• Uses of Inheritance

• Dynamism

• Dynamic Typing

• Dynamic Binding

• Dynamic Loading

• Outlet Connections

• Extrinsic and Intrinsic Connections

• Activating the Object Network

• Aggregation and Decomposition

• Models and Frameworks

• Collaboration

• Organizing Object-Oriented Projects

• Designing on a Large Scale

• Separating the Interface from the Implementation

• Modularizing the Work

• Keeping the Interface Simple

• Making Decisions Dynamically

• Inheriting Generic Code

• Reusing Tested Code