As we have noted many times now, all the points on the PPF represent outcomes that are the result of efficient resource utilization. A society, country, company or individual can produce at levels below its PPF if it is inefficient in using all available resources, or if it leaves some resources unemployed. This region is shaded green, in the graph to the right, and labeled Inefficient. The PPF and the region underneath, taken together, are all the production possibilities available to this society. This is sometimes termed the Production Possibilities Set. Any point within this set is attainable.
Points above the PPF cannot be attained with current resources and technology. A portion of this region is shaded blue, in the graph to the right, and labeled Unobtainable. Unless more resources are acquired or technology improves, these levels of output cannot be attained. This region extends infinitely up and to the right, but for obvious reasons we can't illustrate the entirety of this infinite region. With economic growth and/or technological change, a PPF can be expanded so that outcomes that were previously unobtainable become feasible.