Here the meaning of normalization is not the statistical means of the normalization. It simple means that that the method is converted into some mechanism such that other method can call them irrespective of their residence i.e. residing on same address space or remote address space.
More specifically CORBA uses an interface definition language (IDL) to specify the interfaces which objects present to the outer world. CORBA then specifies a mapping from IDL to a specific implementation language like C++ or Java. Standard mappings exist for Ada, C, C++, Lisp, Ruby, Smalltalk, Java, COBOL, PL/I and Python. There are also non-standard mappings for Perl, Visual Basic, Erlang, and Tcl implemented by object request brokers (ORBs) written for those languages.