Final answer:
The demand curve shows the relationship between product demand and product price. It depicts the quantity of product customers will buy in a market during a period of time even if other factors change.
Step-by-step explanation:
The demand curve is a graphical representation of the relationship between product demand and product price. It shows the quantity of product customers will buy in a market during a period of time even if other factors change. Nearly all demand curves slope downward from left to right, illustrating the law of demand: as the price increases, the quantity demanded decreases, and vice versa.