In the United States and other developed countries, there are three basic philosophies of macroeconomic stabilization. Each of them was present in some form during the Great Depression, and each survives to this day.
The first is Keynesianism, which centers around fiscal stimulus, mainly in the form of increased government spending.
The second is monetarism, which holds that getting economies out of recession is the job of the central bank, which can lower interest rates, engage in quantitative easing or ease monetary policy in other ways.