What is harrod-domar theory?

The Harrod-Domar theory is an economic model that explains how investment can lead to economic growth. It posits that the level of investment needed to achieve a certain growth rate depends on the economy's capital-output ratio and the savings rate. Essentially, it suggests that higher savings and investment lead to increased production capacity, thereby fostering economic expansion. However, it has been criticized for its simplicity and assumptions, particularly regarding the relationship between savings and investment.