Function names, examples, operating system commands, mathematical symbols, and code fragments are shown in a Courier font. Ellipses are used in code examples to indicate that some part of the code is missing.
Throughout the documentation, there are frequent references to "self," which should be understood to mean *this.
The following convention is used to show that class A inherits from class B:
A 
B
When a class inherits from more than one class, or there are multiple levels of inheritance, all of its inheritance relationships are shown. For example, the following illustration indicates that class A inherits from class B and from class C, which inherits from class D.
B
A
C D
The notation system used in the inheritance hierarchies is based on the Object Modeling Technique (OMT) developed by Rumbaugh and others.1