Whereas in ActiveWorlds it is only possible to communicate with users within a 200-meter radius, Atmosphere users could chat with all the users in the world. This model was more appropriate for Atmosphere, considering the smaller sizes of most worlds. Technically, users could chat with anyone in the same YACP "channel", a reference to the IRC protocol (see below). The exception was when worlds would receive too many visitors, as was often the case at "HomeWorld": worlds would "clone", creating duplicate channels for the same world, which would often cause confusion for users. Some world developers wrote scripts that limited communication to users within a certain distance, for greater realism.