The CORBA Namespace Most of the CORBA classes are defined inside the CORBA namespace. For compilers that do not support namespaces, 'CORBA' is implemented as a class that contains all other classes. The CORBA namespace contains classes that implement the core of CORBA - the ORB, the portable data types, etc. Some classes are stored in other namespaces (e.g. POA is under the PortableServer namespace).