Points that are either on the production possibility frontier line or under it are known as what?

The term that describes points that are either on the production possibility frontier (PPF) line or under it is "attainable points." This concept is crucial in understanding the PPF because it represents the combinations of two goods that can be produced using available resources and technology.

When a point lies on the PPF, it indicates that the economy is using its resources efficiently, producing the maximum possible output. Points that fall below the PPF line are considered attainable but reflect inefficiency, where resources are not being fully utilized. Therefore, both scenarios of being on or beneath the frontier are encompassed by the term "attainable points," highlighting the range of feasible production levels.

Points that fall above the PPF are unattainable with the current resources and technology, thus they are considered infeasible. The idea of optimal points typically refers to producing at a specific point on the frontier that aligns with societal preferences, which is not necessarily covered by the broader concept of attainable points. Consequently, "attainable points" effectively captures all combinations of production within the limits of feasibility established by the PPF.