The HB++ language has more than 70 build-in classes that allow you to access the majority of the Palm OS© system functionality. The diagram below shows them in a derivation tree. You can click directly on a class name to access its description. The classes whose name is in italics are not instantiable, whilst the classes whose name is bold are instantiable.

Each class is introduced by a page presenting important information which is not found anywhere else. It is therefore advisable when searching information about a method, a function, a property or an event to also read its introductory page.

Don't forget that the inheritance mechanism makes that certain class functionalities come from its parent classes. For example you can draw in a bitmap by calling none of the functions defined in the Bitmap object, but in the Display object. Also, to help you navigate in the documentation, each introduction page contains in addition to the members of its own class, a link to all the members inherited from the parent classes.