The Prisoner's Dilemma is a thought experiment where two people suspected of a crime are held separately. If both confess, they receive a punishment. If one confesses while the other refuses, the former is released while the latter is punished. If both refuse to confess, then they receive a minor punishment. It is a demonstration of game theory and how one would strategize without knowing the actions of the other person. There is literature written about this which poses various forms of analysis.