As I kept seeing people confuse EDDB with EDDN, and in general not know how game data gets from players to the various third party sites I've made an infrographic.
As per the notes at the bottom this doesn't cover every possible interaction between every possible tool and every possible website. It's intended to just make it clear what the general flow is.
Official URL is: https://ed.miggy.org/misc/EDDN_Dataflow.png
This work is licensed under the Creative Commons Attribution 4.0 International license. See file: LICENSE-CC-BY-4.0.html (also at https://creativecommons.org/licenses/by/4.0/legalcode).
The image is currently created, and maintained, using the program 'dia' http://live.gnome.org/Dia