The term "cannot" is a contraction of "can" and "not," indicating an inability or impossibility to perform an action. It is often used to express limitations, whether physical, mental, or situational. For example, a person might say, "I cannot lift this heavy box," meaning they lack the strength to do so. In written and spoken language, "cannot" is commonly used to convey rules or restrictions. For instance, a sign might read, "You cannot park here," indicating that parking in that area is not allowed. This usage helps clarify expectations and boundaries in various contexts, such as laws, instructions, or social norms.