The key in making great and growable systems is much more to design how its modules communicate rather than what their internal properties and behaviors should be.
A Smalltalk system is a collection of entities communicating with each other through messages. That’s all, there is nothing more.
|• Communicating entities|
|• Message send definitions|
|• Message to string entities|
|• Messages to number entities|
|• A brief introduction to the system Browser|
|• Spacewar! models|