The demand curve is a graphical representation that shows the relationship between the price of a good and the quantity of that good that consumers are willing to purchase at various prices. It is generally downward sloping from left to right, highlighting the inverse relationship between price and quantity demanded. This relationship is underpinned by the law of demand, which states that, ceteris paribus, as price falls, the quantity demanded rises, and vice versa.
As for the price elasticity of demand, the demand curve can showcase different elasticity behaviors at different points. For instance, a vertical demand curve signifies perfectly inelastic demand, meaning quantity demanded does not change as price changes. Conversely, a horizontal demand curve indicates perfectly elastic demand, where a slight change in price leads to an infinite change in quantity demanded. Understanding the shape of the demand curve is crucial when evaluating how changes in price will impact demand.