Well-being is what is ultimately good for a person. Also called prudential value and welfare, it is a measure of how good a person's life is going for them, both in a positive and a negative sense.[1] In its positive sense, well-being is sometimes contrasted with ill-being as its opposite.[2] The term "subjective well-being" denotes how people experience and evaluate their lives, usually measured in relation to self-reported well-being obtained through questionnaires.[3][4][5]