...and one of the ways you can communicate such coupling is by diagramming the (complex) system's design. Google for "linux kernel diagram"[1]. It's quite well

...and one of the ways you can communicate such coupling is by diagramming the (complex) system's design. Google for "linux kernel diagram"[1]. It's quite well designed, displays loose coupling, high cohesion, and all the other things we like about good complex systems. If I want to dig in and start working on a module, I'd still have to understand the relationship between all the bits I work directly with (and probably some that are further away). Don't confuse loose coupling with low complexity. https://www.google.com/search?q=linux+kernel+diagram https://www.google.com/search?q=linux+kernel+diagram