Changes in quantity supplied refer to movements along the supply curve due to changes in price. When the price of a good or service increases, the quantity supplied also increases, and when the price decreases, the quantity supplied decreases. Factors that can influence changes in quantity supplied include the elasticity of supply and demand, government regulation, and changes in input costs. It is important to note that changes in quantity supplied are different from changes in supply, which refer to shifts in the entire supply curve due to factors such as changes in technology or production costs.