The term “mutually exclusive” is a term used to describe two events that cannot both be true to occur. A coin flip is an example of a mutually exclusive event. A flipped coin cannot read both heads and tails at the same time. The probability of a coin flip reading both heads and tails would be zero, but the probability of a coin flip reading heads or tails would be the sum of each individual probability. The term is often used in logic and probability theory.