This document discusses fiscal and monetary policy tools used by governments and central banks to influence aggregate demand and stabilize economies. Fiscal policy tools include changes to government spending and taxes by Congress and the President. Monetary policy tools are used by the Federal Reserve and include open market operations, reserve requirements, and interest rates. Both fiscal and monetary policies can be either expansionary or contractionary depending on whether their goal is to increase or decrease aggregate demand to address recessionary or inflationary gaps in the economy.