Since human beings are purposeful creatures, the study of incentive structures is central to the study of all economic activity (both in terms of individual decision-making and in terms of co-operation and competition within a larger institutional structure). Economic analysis, then, of the differences between societies (and between different organizations within a society) largely amounts to characterizing the differences in incentive structures faced by individuals involved in these collective efforts. Ultimately, incentives aim to provide value for money and contribute to organizational success.

Incentives can be classified according to the different ways in which they motivate agents to take a particular course of action. One common and useful taxonomy divides incentives into four broad classes:

(There is another common usage in which incentive is contrasted with coercion, as when economic moralists contrast incentive-driven work—such as entrepreneurship, employment, or volunteering motivated by remunerative, moral, or personal incentives—with coerced work—such as slavery or serfdom, where work is motivated by the threat or use of violence, pain and/or deprivation. In this usage, the category of "coercive incentives" is excluded. For the purposes of this article, however, "incentive" is used in the broader sense defined above.)

Francois Henri "Jack" LaLanne (September 26, 1914 – January 23, 2011) was an American fitness, exercise, and nutritional expert and motivational speaker who is sometimes called "the godfather of fitness" and the "first fitness superhero." He described himself as being a "sugarholic" and a "junk food junkie" until he was 15. He also had behavioral problems, but "turned his life around" after listening to a public lecture by Paul Bragg, a well-known nutrition speaker. During his career, he came to believe that the country's overall health depended on the health of its population, writing that "physical culture and nutrition — is the salvation of America."

Decades before fitness began being promoted by celebrities like Jane Fonda and Richard Simmons, LaLanne was already widely recognized for publicly preaching the health benefits of regular exercise and a good diet. He published numerous books on fitness and hosted a fitness television show between 1951 and 1985. As early as 1936, at age 21, he opened one of the nation's first fitness gyms in Oakland, California, which became a prototype for dozens of similar gyms using his name. One of his 1950s television exercise programs was aimed toward women, whom he also encouraged to join his health clubs. He invented a number of exercise machines, including leg-extension and pulley devices. Besides producing his own series of videos, he coached the elderly and disabled to not forgo exercise, believing it would enable them to enhance their strength.