Macroeconomics is a branch of economics that deals with the performance, structure, behavior, and decision-making of an economy as a whole. It focuses on the aggregate changes in the economy such as unemployment, growth rate, gross domestic product (GDP), and inflation. Macroeconomics attempts to measure how well an economy is performing, understand what forces drive it, and project how performance can improve. Some of the key questions addressed by macroeconomics include: What causes unemployment? What causes inflation? What creates or stimulates economic growth? . Macroeconomics is used to evaluate the performance and stability of local, national, and global economies.

Macroeconomics is different from microeconomics, which is more focused on the influences on and choices made by individual actors in the economy (people, companies, industries, etc.) . Microeconomics is concerned with how supply and demand interact in individual markets for goods and services.

Macroeconomics analyzes all aggregate indicators and the microeconomic factors that influence the economy. Governments and corporations use macroeconomic models to help in formulating economic policies and strategies. The Federal Reserve closely examines macroeconomics because its goals, such as maximum sustainable employment and stable inflation, are measured and achieved on an economy-wide level, not on an individual level.

Macroeconomics as a separate field of research and study is generally recognized to start in 1936, when John Maynard Keynes published his The General Theory of Employment, Interest and Money, but its intellectual predecessors are much older. Since World War II, various macroeconomic schools of thought like Keynesians, monetarists, new classical and new Keynesian economists have made contributions to the development of the macroeconomic research mainstream.