Due to the .NET Framework, the Visual RPG language supports inheritance (extensibility), the ability to define classes that serve as the basis for derived classes. Derived classes inherit, or can extend, the properties, methods, and events of the base class. In Visual RPG, the Extends keyword in used when declaring a class (BEGCLASS) to inherit, or extend. Derived classes can also override inherited methods with new implementations. All classes created with Visual RPG are extendable by default.
Extensibility allows you to write and debug a class once, and then reuse that code over and over as the basis of new classes. Inheritance also allows you the ability to define classes that can be used interchangeably by client code at run-time, but with functionally different, yet identically named methods or properties.