Looking for the plugin's name

So I honestly didn't know where to post this and.. i'm notmoving it-

You know how..let's use Hive for an example:
You can right-click the signs and they bring you to a server like map with players in it and it can get full. I have some questions about that.
1) is the arenas that they built and you get teleported to, even in the same map? lol because when you think of where the areas are and you wonder if you would be able to see other player's nameplates if they were close enough.. or is it in a new realm or something like a copy of the overworld?
(sorry if this is very jumbled)
But basically i wanna know what plugin that is

 

Maybe im wrong but i think you're talking about Bungee Cord.
Servers like hypixel or shotbow are using plugins like that ^^

 

Yeah! What is the plugin name?