Instructors' Guide

Introduction Terminology Expressions Control Objects Inheritance Technology Summary


The introduction of Smalltalk came along with an, at the time, astounding terminology. See slide sm-terminology.



slide: Smalltalk -- terminology

Most important is the notion of object, which is something that acts in response to messages (by executing a method procedure). In Smalltalk, everything is an object. Moreover, every object is an instance of a class. A class is the description of a collection of objects which share the same structure and applicable methods. The methods of both objects and classes (considered as an object) are grouped in so-called protocols. Related collections of classes may be grouped in so-called categories. Both protocols and categories are merely syntactic add-ons, meant to facilitate programming.