Ruby in a Nutshell

Name

class Statement

Synopsis

class class_name [< superclass]
code
end

Defines a class. A class_name must be a constant. The defined class is assigned to that constant. If a class of the same name already exists, the class and superclass must match, or the superclass must not be specified, in order for the features of the new class definition to be added to the existing class. class statements introduce a new scope for local variables.