Macroeconomics looks at the big picture of the entire economy. Instead of studying individual consumers or businesses (that is microeconomics), macro studies aggregate phenomena — total output (GDP), overall price levels (inflation), national unemployment, international trade, and government fiscal/monetary policies.
Key questions macroeconomics answers: Why do economies grow? What causes recessions? Why does inflation happen? How does government spending affect employment? The field was largely invented by John Maynard Keynes during the Great Depression when he argued that government intervention could stabilize the economy.
Two major schools of thought dominate: Keynesian economics (government should actively manage the economy through spending and taxation) and monetarism/neoclassical (markets self-correct; the central bank should focus on controlling the money supply). Modern macroeconomic policy typically blends elements of both approaches.