The Phillips Curve is an economic concept that illustrates the inverse relationship between inflation and unemployment. It suggests that when unemployment is low, inflation tends to be high, and vice versa. This relationship implies that policymakers may face a trade-off between controlling inflation and reducing unemployment. Originally developed by economist A.W. Phillips in 1958, the curve has evolved over time. In the short run, it can be useful for understanding economic fluctuations, but in the long run, many economists argue that the relationship may not hold due to factors like expectations and supply shocks.