Happiness and utility are two ways to measure how good someone feels about their life. Happiness is based on how people feel overall, while utility is based on what they actually do. There are three main differences between happiness and utility: (1) Happiness depends on what people have in their life, while utility only looks at what can be bought. (2) Happiness is about how people feel now, while utility is about how they think they will feel in the future. (3) Happiness is limited because it's tied to specific needs, while utility is unlimited because it's based on what people want in the future. It's important to consider these differences when studying well-being.