Monetary policy uses various tools like interest rates, bank rates, cash reserve ratios, and statutory liquidity ratios to control the supply of money and credit in an economy. The goals are to maintain stable prices and low unemployment. Expansionary policy increases the money supply to boost the economy and combat unemployment during recessions by lowering interest rates. Contractionary policy decreases the money supply or slowly increases it to combat inflation by raising interest rates. In India, the Reserve Bank of India uses tools like repo rates, reverse repo rates, cash reserve ratios, and statutory liquidity ratios to influence monetary conditions.