OMG Interface Definition Language (IDL) file
IDL (interface definition language) is a generic term for a language that lets a program or object written in one language communicate with another program written in another unknown language. In distributed object technology, it's important that new objects be able to be sent to any platform environment and discover how to run in that environment.
An Object Request Broker (ORB) is one example of a program that would use an interface definition language to "broker" communication between one object program and another one.
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