Tight, or contractionary policy is a course of action by a central bank to slow down economic growth, constrict spending in an economy that is seen to be accelerating too quickly, or curb inflation when it is rising too fast. The Fed tightens monetary policy by raising short-term interest rates through policy changes to the discount rate, also known as the federal funds rate. The Fed may also sell assets on the central bank's balance sheet to the market through open market operations (OMO). Tapering refers to the period of reversal between expansionary policy and contractionary monetary policy.