Economic problems can be analysed or studied in two ways—(i) at individual level, and (ii) at aggregate level. The method of studying at an individual level is known as Micro-Economics and that of studying at an aggregate or collective level is known as Macro-Economics.
Micro Economics studies the problems of individual economic units such as a firm, an industry, a consumer etc. Macro Economics studies economic problems relating to an economy viz., National Income, Total Savings etc.
Micro and Macro these terms were first used by the Swedish economist Rognar Frisch in 1920s to represent the "level of aggregation" of economic variables analyzed in an economic problem. The word micro means "small", while macro stands for "large".