Mental poker is the common name for a set of cryptographic problems that concerns playing a fair game over distance without the need for a trusted third party. The term is also applied to the theories surrounding these problems and their possible solutions.
Having a "poker face" in life can have both positive and negative implications, depending on the context. On the positive side, a poker face can help you maintain composure and control your emotions in situations where it's important to remain stoic and focused, such as negotiations or high-pressure environments.