Persistent world

The real world is persistent. The game world of a pervasive game takes place in the real world and so pervasive games are also persistent. In other words, pervasive games share the persistence trait with virtual worlds. An example of a pervasive game that makes heavy use of a virtual world is Can You See Me Now?, where street runners exist in a virtual world while simultaneously running around the real physical world; the game was persistent during play, as well as the virtual world. == Simulated persistence ==

To give the illusion that the game world is always available, persistence can be simulated. This can be achieved by scheduling when players are allowed to play, around times when the world is offline, or as in the Animal Crossing series, having the game generate events that could have happened during the period of inactivity. Aside from virtual worlds, the simulation of a persistent world is also possible in single player games. In Noctis, players are advised to turn off the game while refueling because it takes so long. In addition, if a player who has landed on a planet stops playing and then after a while resumes, he or she can see visible changes in the sea level or the daytime/nighttime cycle. A form of simulated persistence referred to as "pseudo-persistence" has been used in both video games and pervasive games. Pseudo-persistence means making relevant world data available when the relevant players reconnect to the world instance. In a mobile game, a virtual world might exist on a distributed collection of mobile devices. If a player reconnects to a device they previously connected to, they find that their relevant world data is still present. == First virtual worlds ==

The first multi-player game to demonstrate on-line persistence was the text-based MUD1 written in 1978 by Rob Trubshaw and Richard Bartle. Initially only available for a few hours in off-peak time at Essex University, UK, it featured a world reset every 105 minutes. Nevertheless, it persisted independent of players logging in for the time it was running. The subsequent decade saw many on-line worlds clone this template, but all featured variations on timed resets and reboots or did not allow players to retain objects within the game other than running point totals such as treasure or experience points as a marker of progress. Avalon: The Legend Lives can be considered the first game to introduce a true persistent state world in 1989. Avalon pioneered the ability for items to be retained by the player whilst offline while the Avalon realm at large continued 24/7 with only a morning backup to mark the world pausing briefly. It is currently the longest running online virtual world. == See also ==