In an attempt to simply the terminology in the fediverse, I propose we start referring to "instances" as "neighborhoods". Here's a short pitch:
* Has its own set of rules.
* Has its own "guard" (sysadmin) that makes sure there are no incidents.
* Is usually (but not always) focused on a common theme.
You can send an update to:
1. A specific person.
2. Your own neighborhood.
3. Entire network.
IMO this proposal would make things about 30% easier to understand for newcomers.