Rails ships with some handy features, and most of that functionality is there because we have common problems; and those problems need a default solution. You need quick two-way communication between your client and server. Action Cable can solve that quickly, and get you up and productive with out setting up expensive external add-ons and complex integrations.
This magic is wonderful until you need to untangle how websockets, connections, channels, consumers, and clients all fit together. Let's look under the hood and see how everything is woven together.