Message-passing is often at the heart of dynamic programming languages like Objective-C. For example, the ObjC runtime (also described here) is a library for creating instances of objects, obtaining "selectors" to the names of message-receivers (methods) that the object can process, and even do some MOP operations on the objects.
In more widespread distributed systems literature, this is often called "message-oriented middleware" and typically involves messages dispatched over network links to "queues" where they are stored until examined (and possibly consumed) by messaging clients. Those who produce messages are often called "producers"; those who consume them, "consumers".
Last modified 06 April 2022