The driving force in the economy is Enterpreneurship.
The four factors of production, used to produce goods and services, are land, labor, capital and enterpreneurship.
Land represents the natural resources, such as the physical place where production happens and every natural good used to produce. These resources can be renewable, such as wood, or non renewable, such as oil.
Labor is the work put into producing goods. It represents the people who transform resources into goods and services--from the baker to the farmer, from the hotelier to the engineer.
Capital is the funds invested, as well as the equipment and buildings that are used to make production possible. Without capital, labor and land cannot be purchased, and workers have no tools to work with.
Finally, there is Enterpreneurship. The enterpreneur is responsible of combining the other three factors to earn a profit. Without this step, the economy does not go forward. They innovate and create businesses, generating economic growth.