While the object system is general enough to describe all standardized classes (including, for example, number, hash-table, and symbol), the next figure contains a list of classes that are especially relevant to understanding the object system.
Figure 4-7. Object System Classes
built-in-class method-combination standard-object
class standard-class structure-class
generic-function standard-generic-function structure-object
method standard-method
4.3.3 Creating Instances of Classes
4.3.5 Determining the Class Precedence List