Clients
A client of an object has access to an object reference for the object, and invokes operations on the object. A client knows only the logical structure of the object according to its interface and experiences the behavior of the object through invocations.
Java clients see objects and ORB interfaces through the perspective of the language mapping, bringing the ORB right up to the programmer's level. Clients are maximally portable.
Client code has no knowledge of the implementation of the object or which ORB is used to access the implementation.