A Neverwinter Nights 2 Persistent World is any hosted module that is not using "as is" campaign modules from the the OC or MOTB. While considered similar to a Multiplayer Online Roleplaying Game (MMORPG) and generally playable 24 hours a day, the number of players is very small in comparison. Many Persistent Worlds are highly customized, each following the vision of their developer, with customized classes, gods, races, encounters, and stories. The majority are in the role playing and story categories, but there are PWs for every style of play.