Role-playing refers to the changing of one's behavior to assume a role, either unconsciously to fill a social role, or consciously to act out an adopted role.
A role-playing game is a game in which the participants assume the roles of characters and collaboratively create 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, they may improvise freely; their choices shape the direction and outcome of the games.
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