Perhaps the first virtual world to use instances was the MMORPG
The Realm Online, launched in 1996. Combat in this game was extensively instanced, with every battle taking place in a special room outside of the open world. In
Guild Wars, Town/Outpost areas are created on demand, with a new "district" of that town being created for every 100 players in it; players can move between these at will. When entering an Explorable Area or Cooperative Mission, a separate instance will be created for each group (ranging in size from 2 to 12) of players. Players can play with players across the globe, as in
EVE Online, along with the advantages in load scaling and resources of a traditional multiple server model for
ArenaNet, the developers. In
RuneScape, instances are used mostly in quests, so that other players cannot interfere with the player who is doing the quest, such as battling boss
NPCs or having to accomplish a special task. They are also used in certain 'minigames'. However, most monsters not related to quests are not instanced, so players often have to compete with each other to get the reward from killing them. They are also used extensively in the new skill Dungeoneering. The player-owned-houses (commonly abbreviated as P.O.H.), houses that can be owned and built by players, are instanced, with each house having its own instance.
Wizard101 has a unique system for its instances. As soon as a player steps on the entry area, ten seconds are given for up to three other players to enter. Once inside, the instance usually triggers a new line of quests, which must be completed to gain access to other parts of the instance. If a player logs out or leaves through the "front door", progress will be reset (a warning message will appear). If a player dies, flees, or teleports, data will then be reset in 30 minutes. If a monster is defeated in an instance, it stays defeated. Players can repeat instances as many times as they want. ==See also==