Macroeconomics is a branch of economics dealing with the performance, structure, behavior, and decision-making of an economy as a whole. This includes regional, national, and global economies.
Macroeconomics is a branch of the economics field that studies how the aggregate economy behaves. In macroeconomics, a variety of economy-wide phenomena is thoroughly examined such as, inflation, price levels, rate of growth, national income, gross domestic product and changes in unemployment.
Macroeconomics differs from microeconomics, which focuses on smaller factors that affect choices made by individuals and companies. Factors studied in both microeconomics and macroeconomics typically have an influence on one another. For example, the unemployment level in the economy as a whole has an effect on the supply of workers from which a company can hire. Macroeconomics, in its most basic sense, is the branch of economics that deals with the structure, performance, behavior and decision-making of the whole, or aggregate, economy, instead of focusing on individual markets.
Those working in the field of macroeconomics study aggregated indicators such as unemployment rates, GDP and price indices, and then analyze how different sectors of the economy relate to one another to understand how the economy functions. Macroeconomists develop models explaining relationships between a variety of factors such as consumption, inflation, savings, investments, international trade and finance, national income and output. Contrarily, microeconomics analyzes how individual agents act, namely consumers and corporations, and studies how these agents' behavior affects quantities and prices in certain markets. Such macroeconomic models, and what the models forecast, are used by government entities to aid in the construction and evaluation of economic policy.
Macroeconomics is a rather broad field, but two specific areas of research are representative of this discipline. One area involves the process of understanding the causation and consequences of short-term fluctuations in national income, also known as the business cycle. The other area involves the process by which macroeconomics attempts to understand the factors that determine long-term economic growth, or increases in the national income.
Macroeconomics, as it is in its modern form, started with John Maynard Keynes and the publication of his book "General Theory of Employment, Interest and Money" in 1936. Keynes offered an explanation for fallout from the Great Depression, when goods remained unsold and workers unemployed, a feat that left classical economists stumped. Keynes' theory explained why markets may not clear. This theory evolved throughout the 20th century, diverting into several macroeconomic schools of thought known as Keynesian economics, often referred to as Keynesian theory or Keynesianism.