Let's say there's a group of people in your hometown who like dogs. They will talk about dog thing this, dog thing that, probably something local. Now you travel to another town and they too have a group that likes dogs. They will talk about dog things too, but probably it'll be different dog things that are also specific to their location.
You have the option to join both dog communities without physically traveling from one town to another. You can even choose not to join a dog group in another town that only like to talk about dog fighting for example.
There is no "tech savvy" required here. You signed up in a town that has communities there, you can see communities from other towns, and you can choose to join them all, some, or none. It's up to you.