coherence provides two types of online replication services: Rooms and Worlds. Read about the different uses cases for each
Rooms are best for session-based gameplay where the match between players takes place in a short-lived environment.
A good example is a first person shooter multiplayer match. The match takes place between two teams in a single game session, and players enter through a lobby and matchmaking. When the match is concluded, the multiplayer environment the match took place in is closed and players return to a lobby.
This is one example of how Rooms can be used, but it is by no means the only use case. The important distinction between Rooms and Worlds (see below) is that Rooms are relatively short-lived and are meant to be created and closed by the game client through the coherence SDK.
See Rooms API.
Worlds, as opposed to Rooms, are long-lived and permanent multiplayer environments provided by coherence. Using the Developer Portal, your project will easily define and manage your World configurations.
See Manage Worlds.
A good example of a World is a permanent environment for an Massively Multiplayer Game (MMO). Regardless of the number of players connected, the environment is always available, and players can connect and disconnect at will.
Entities can be permanently saved in the world so that even if there are no active connections, they are persisted when players do connect.
See Worlds API.
Your project does not have to choose one-or-the-other. A project in coherence can contain both World and Rooms.
A good example of this scenario is again, our MMO. Although players connect to a permanent and persistent World, they may enter a dungeon instance with other players. These dungeon instances can be Rooms.
The primary difference in the configuration and usage of Room and Worlds is that Worlds are managed in the Developer Portal, whereas Rooms are created and managed through the SDK.