Macroeconomics emerged as a major branch of economics during the world depression of the 1930s. The severe economic problems of the time lent importance to the subject matter of macroeconomics--the behavior of the economy as a whole. A book by John Maynard Keynes, The General Theory of Employment, Interest, and Money, developed a framework in which to systematically consider the behavior of aggregate economic variables such as employment and output. During the two decades following World War II, Keynes's followers elaborated and extended his theories. From the first there were skeptics, perhaps most notably Milton Friedman, but Keynesian economics became the orthodox mode of thinking about macroeconomic questions.
The years since the late 1960s, however, have witnessed major challenges to keynesian economics, In the 1970s there was increased interest in monetarism, the body of theory of theory Milton Friedman and others had developed beginning in the 1940s. A new school of macroeconomic theory, the new classical economics also came on the scene during the 1970s.
In the 1980s, Keynesian policy prescriptions came under attack from a group called the supply-side economists. The 1980s also witnessed the development of two new lines of macroeconomic research: the real business cycle theory and the new Keynesian economics.
Part 1 Introduction and Measurement
Part 2 Classical Economics and The Keynesian Revolution
Part 3 Macroeconomic Theory After Keynes
Part 4 Open Economy Macroecnomics
Part 5 Economic Policy
Part 6 Microeconomics Foundations