<programming> (ORB) Part of the OMG CORBA specification, an ORB's basic function is to pass method invocation requests to the correct objects and return the results to the caller. To achieve this the ORB must be able must be able to identify and locate objects, handle connections from invoker and the data returned from methods. Communication between the ORB and applications are achieved through IDL stubs and skeletons whilst the OMG has specified IIOP as the protocol through which ORBs may communicate with each other. Using IIOP, an ORB may request method invocations from a remote object. (2003-11-21)

In distributed computing, an object request broker (ORB) is a middleware which allows program calls to be made from one computer to another via a computer network, providing location transparency through remote procedure calls. ORBs promote interoperability of distributed object systems, enabling such systems to be built by piecing together objects from different vendors, while different parts communicate with each other via the ORB.

<standard, programming> (CORBA) An Object Management Group specification which provides a standard messaging interface between distributed objects. The original CORBA specification (1.1) has been revised through version 2 (CORBA 2) with the latest specification being version 3 (CORBA 3). In its most basic form CORBA consists of the Interface Definition Language (IDL) and the Dynamic Invocation Interface (DII). The IDL definition is complied into a Stub (client) and Skeleton (server) component that communicate through an Object Request Broker (ORB). When an ORB determines that a request is to a remote object, it may execute the request by communicating with the remote ORB. The Corba IDL can be mapped to a number of languages including C, C++, Java, COBOL, Smalltalk, Ada, Lisp, Python, and IDLscript. CORBA ORBs are widely available for a number of platforms. The OMG standard for inter-ORB communication is IIOP, this ensures that all CORBA 2 compliant ORBS are able to interoperate. Latest version: Corba 3.0.3 2004-03-12, as of 2007-09-04. See also COSS, Component Object Model, RMI. {OMG CORBA specs (http://www.omg.org/technology/documents/corba_spec_catalog.htm)}. (2007-09-04)