A role-playing game (RPG, often roleplaying game) is a type of game in which the participants assume the roles of fictional characters and collaboratively create or follow stories. Participants determine the actions of their characters based on their characterization, and the actions succeed or fail according to a formal system of rules and guidelines. Within the rules, players can improvise freely; their choices shape the direction and outcome of the games.
An online text-based role playing game (OTBRPG) is a role-playing game played online using a solely text-based interface such as TELNET, an internet forum, or in a chat. Online text-based role playing games predate graphical online games by several years, and can be attributed to the first attempts to bring multiplayer gaming to the internet, which culminated in the invention of MUDs, the forefather of MMORPGs.