.. Copyright (C) 2020: ALbert Mietus. Introduction ============ An almost trivial example of PubSub is the daily newspaper: Once you have a subscription, you automatically get each new publication. Typically, you are not the only subscriber; the *same* ‘newspaper’ is sent to all subscribers: everybody got his *copy*. And, whenever somebody cancels his subscription, all others still get there update daily. |BR| Also notice: your copy is independent of that the neighbors. And, until you subscribe, the publisher does not know you. In software-engineering, we call that **uncoupled** or *loosely coupled*, and that is great. |BR| As we will explain in the next page. .. uml:: PubSub-newspaper.puml .. toctree:: :maxdepth: 2 advantages Use API