In the economic sense, the social phenomenon of individual human beings or organizations each concentrating their productive efforts on a rather limited range of tasks. Specialization entails focussing on a narrow area of knowledge or skill or activity. It involves a person's or an organization's adapting for the unusually effective or efficient performance of some particular function, often at the expense of the individual's or organization's ability to perform most other functions for themselves, which are then necessarily left to others with more appropriate skills or talents or abilities. [For a related concept, see division of labor.] Like the division of labor, specialization generally comes about because it is discovered (usually by trial and error) that the individuals or groups concerned can increase their productivity (and hence, under a market economy, their incomes) through greater specialization according to the principle of comparative advantage.