The number one is often regarded as the symbol of unity and undividedness, a starting point or even the essence of singularity in mathematics. Yet the meaning of 'one' in our daily lives is surprisingly relative and context-dependent. For example, consider the simple act of drinking a beer. When we say "I drink one beer," this can refer to either consuming a single glass of beer or to a set of four glasses of beer taken together as one whole. This reveals an intriguing property of the number one: it can simultaneously express a singular and a plural, depending on the context in which it is used.