What is fiscal policy in economics and political science?

In economics and political science, fiscal policy is the use of government revenue collection (taxes or tax cuts) and expenditure to influence a country's economy. The use of government revenue expenditures to influence macroeconomic variables developed in reaction to the Great Depression of the 1930s, when the previous laissez-faire approach to economic management became unworkable. Fiscal policy is based on the theories of the British economist John Maynard Keynes, whose Keynesian economics theorised that government changes in the levels of taxation and government spending influence aggregate demand and the level of economic activity. Fiscal and monetary policy are the key strategies used by a country's government and central bank to advance its economic objectives. The combination of these policies enables these authorities to target inflation (which is considered "healthy" at the level in the range 2%–3%) and to increase employment. Additionally, it is designed to try to keep GDP growth at 2%–3% and the unemployment rate near the natural unemployment rate of 4%–5%. This implies that fiscal policy is used to stabilise the economy over the course of the business cycle.

Changes in the level and composition of taxation and government spending can affect macroeconomic variables, including:

aggregate demand and the level of economic activity
saving and investment
income distribution
allocation of resources.
Fiscal policy can be distinguished from monetary policy, in that fiscal policy deals with taxation and government spending and is often administered by a government department; while monetary policy deals with the money supply, interest rates and is often administered by a country's central bank. Both fiscal and monetary policies influence a country's economic performance.