The concept of entrepreneurship has evolved over time. Early economists like Cantillon and Smith discussed the roles of entrepreneurs but did not use the term. Cantillon identified entrepreneurs as coordinating producers and consumers under uncertainty. Schumpeter's work in the 1920s emphasized the innovating and disruptive functions of entrepreneurs through new combinations. Modern views see entrepreneurs as discovering opportunities through alertness to introduce new products, markets, sources of supply, and more. The nature of entrepreneurship continues developing with focuses on knowledge, competition, and disequilibrium.