concept of new classical school and new keynesian
New Keynesian economics Two main assumptions define the New Keynesian approach to macroeconomics. Like the New Classical approach, New Keynesian macroeconomic analysis usually assumes that households and firms have rational expectations. But the two schools differ in that New Keynesian analysis usually assumes a variety of market failures. In particular, New Keynesians assume that there is imperfect competition[1] in price and wage setting to help explain why prices and wages can become "sticky", which means they do not adjust instantaneously to changes in economic conditions.
Supply-side economics Supply-side economics is a macroeconomic theory arguing that economic growth can be most effectively created by lowering taxes and decreasing regulation.[1][2] According to supply-side economics, consumers will then benefit from a greater supply of goods and services at lower prices and employment will increase.[3] It was started by economist Robert Mundell during the Ronald Reagan administration.