Role-playing game (better known as RPG) is a common term for a whole range of board, video, and online games where players take on imaginary characters set in a fictional environment. Either by acting directly or by describing their actions, they play these roles in a story that can be pre-planned or being generated in real-time. The success or failure of their actions is determined by the agreed system of rules of a particular game.

In the role-playing board games (i.e., pen & paper RPGs), a pioneer RPG gameplay, one of the players takes on the role of game leader or dungeon master. The dungeon master is responsible for storytelling, implementing the rules, and playing all other characters, the players encounter. The same goes for live-action games (so-called live-action RPG or LARP). Instead of describing their characters’ actions, the actors perform it physically, and it is similar to improvisational theater. The most known board role-playing game is Dungeons & Dragons (D&D), originally set in a fantasy world. Still, there are also many of its derivatives and completely different systems.

Role-playing games are also a widespread genre of computer video games. The first such games were MUD – Multi-User Dungeon or. “Multiplayer dungeons,” which combined elements of role-playing, adventure and action games, and online chat rooms, most took place in text mode as players connected to the server and performed tasks by typing in commands. The server described the world and solved actions. Today, most such video games are graphic, intended for either a single-player or multiplayer online play. Some massively multiplayer online role-playing games (Massively Multiplayer Online Role-Playing Games or MMORPGs), such as World of Warcraft, attract millions of players.