The economic study of growth has evolved dramatically. It began with the Neoclassical model, which treated the ultimate source of long-run growth—technology—as an external mystery. It then progressed to the endogenous growth theories, which brought technology inside the economic system, explaining it as the result of intentional, profit-motivated decisions by firms and individuals.

While the models differ in their mechanisms and predictions, they share a unified message: sustained improvements in human living standards are not automatic. They are fueled by our collective ability to create, apply, and spread new knowledge. Understanding the economic forces that foster or hinder this process of innovation remains the central task of growth economics.