A set of classes and their interrelationships. One class may be a specialisation (a "subclass" or "{derived class}") of another which is one of its "{superclasses}" or "base classes". When a method is invoked on an object it is first looked for in the object' s class, then the superclass of that class, and so on up the hierarchy until it is found. Thus a class need only define those methods which are specific to it, and inherits methods from all its superclasses. See also: multiple inheritance. (1997-08-06)
