What is a complement in economics?

In economics, a complement refers to goods that are typically purchased together because they enhance each other's utility. For instance, if a consumer buys a printer, they are likely to also buy printer ink; both products are most useful when used together. This joint demand occurs because the consumption of one good (the printer) increases the consumption of the other (the ink).

Understanding complements is crucial because when the price of one complement rises, the demand for the other may decrease since the overall cost of using the combination of the two goods becomes more expensive for consumers. This interdependence makes it important for businesses and economists to analyze how changes in the market for one good can influence the sales of its complementary goods.