In philosophy, normative statements affirm how things should or ought to be, how to value them, which things are good or bad, which actions are right or wrong. Normative is usually contrasted with positive (i.e. descriptive, explanatory, or constative) when describing types of theories, beliefs, or propositions. Positive statements are factual statements that attempt to describe reality.
For example, "children should eat vegetables", "smoking is bad", and "those who would sacrifice liberty for security deserve neither" are normative claims. On the other hand, "vegetables contain a relatively high proportion of vitamins", "smoking causes cancer", and "a common consequence of sacrificing liberty for security is a loss of both" are positive claims. Whether or not a statement is normative is logically independent of whether it is verified, verifiable, or popularly held.