The Federal Reserve is in charge of monetary policy in the United States.
Contractionary monetary policy slows the rate of growth in the money supply or outright decreases the money supply in order to control inflation; while sometimes necessary, contractionary monetary policy can slow economic growth, increase unemployment and depress borrowing and spending by consumers and businesses.
An example would be the Federal Reserve's intervention in the early 1980s: in order to curb inflation of nearly 15%, the Fed raised its benchmark interest rate to 20%.
This category includes quantitative easing, the purchase of varying financial assets from commercial banks.
In the US, the Fed loaded its balance sheet with trillions of dollars in Treasury notes and mortgage-backed securities between 20.
The latter refers to taxes and government borrowing and spending.
The Federal Reserve has what is commonly referred to as a "dual mandate": to achieve maximum employment (in practice, around 5% unemployment) and stable prices (2-3% inflation).
Monetary policy consists of the actions of a central bank, currency board or other regulatory committee that determine the size and rate of growth of the money supply, which in turn affects interest rates.
Monetary policy is maintained through actions such as modifying the interest rate, buying or selling government bonds, and changing the amount of money banks are required to keep in the vault (bank reserves).
In addition, it aims to keep long-term interest rates relatively low, and since 2009 has served as a bank regulator.
Its core role is to be the lender of last resort, providing banks with liquidity in order to prevent the bank failures and or panics in the financial services sector.
Welfare is a government program which provides financial aid to individuals or groups who cannot support themselves.