demand curve

graph depicting the demand for a product as a function of its price

In economics, the demand curve can be defined as the graph depicting the relationship between the price of a certain commodity, and the amount of it that consumers are willing and able to purchase at that given price (see demand).Demand curves are used to estimate behaviors in competitive markets, and are often combined with supply curves, often to estimate the equilibrium price (the price at which all sellers are able to find a willing buyer, also known as market clearing price) and the equilibrium quantity (the amount of that good or service that will be produced and bought without surplus/excess supply or shortage/excess demand) of that market. Please see the article on Supply and Demand for more details on how this is done.
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a line drawn on a graph to represent the number of units of a product which will be purchased at any particular price point.

A graphical representation of a demand schedule . Conventionally, the demand curve is usually drawn between axes with price plotted along the vertical axis and number of units of the good or service demanded plotted along the horizontal axis. Where the law of demand applies to the particular market under consideration, the demand curve will slope (either gently or steeply) downwards from left to right.
[See also: demand , law of demand , demand schedule , supply ]