This document discusses different types of unemployment including frictional, structural, seasonal, and cyclical unemployment. It also discusses Okun's law and the relationship between inflation and unemployment shown by the Phillips curve. The Phillips curve initially showed an inverse relationship between inflation and unemployment but this broke down in the late 1960s. The long-run Phillips curve is vertical at the natural rate of unemployment. Government policies can affect inflation and unemployment in both the short-run and long-run.