My Harry Potter federation explainer:
Your instance is your House at Hogwarts. The local timeline is a common room shared with the other wizards in your instance.
The federated timeline is the dining hall, your instance + people from other instances, but not the whole wizarding world.
Then the dark Memelord rises & Shitposter.club* dogpiles the Hufflepuffs & @[email protected] has to die & resurrect in an overt Christ analogy to save Mastodon.
It kind of got away from me at the end.