The production possibilities frontier (PPF) is a graphical representation that shows the maximum output combinations of two goods or services that an economy can produce, given fixed resources and technology. The curve illustrates trade-offs, highlighting how producing more of one good requires sacrificing some quantity of another. Points on the PPF indicate efficient production levels, while points inside the curve represent underutilization of resources. Points outside the curve are unattainable with current resources. The PPF can shift due to changes in resource availability or technological advancements, affecting the economy's overall production capacity.