What is the "federated" section?

Yesterday I saw a notification from Dr. J saying one of my questions had been moved to “federated section”. I had never seen any section called “federated” before, and of course it wasn’t visible anywhere. Out of curiosity, I clicked on my question, only to be greeted by the fat jelly-eater king and the “we couldn’t find XXX” sentence.

My question has been back now, but I’m still curious of the “federated” section. Can anyone tell me what it is?