Microeconomics and macroeconomics--micro and macro, as many economists call them--are the two major subdivisions in the field of economics. Micro examines the economy in miniature, while macro concerns itself with economic aggregates, such as gross domestic product or national unemployment rates.
Microeconomics studies the economy in miniature, considering specific sectors or industries, and the interactions of households and firms within these markets.
The major areas of study in microeconomics include firms' optimal production, the impact of public policy on particular markets, and issues related to prices.
Because so much of microeconomics examines issues related to prices of goods and services, micro is sometimes referred to as price theory.
Macroeconomics takes a "big picture" approach to the economy, studying economywide phenomena and issues affecting the economy as a whole.
Major concepts in macroeconomics include unemployment, inflation, productivity, government budget deficits (or surpluses) and gross domestic product (GDP).
Business cycles, a term for fluctuating periods of economic strength and weakness, are a major topic of study in macroeconomics.