How is a change in price of an item showed on the demand curve?

A change in the price of an item is represented by a movement along the demand curve rather than a shift of the curve itself. If the price decreases, there is an increase in the quantity demanded, shown as a movement down the curve; conversely, if the price increases, the quantity demanded decreases, resulting in a movement up the curve. This illustrates the inverse relationship between price and quantity demanded, as outlined by the law of demand.