A graph that depicts the hypothetical supply of a product or service at different price levels. The supply curve usually slopes upward, since higher prices indicate greater returns, giving producers greater incentive to supply products. In the long run, the price-supply tradeoff is greater than in the short run, as firms have more opportunities to adjust to price changes because their supply curves are more elastic. In the short run, an increase in price will usually lead to an increase in supply, but the full extent of the price increase may only be apparent in the long run. At different extremes, the supply curve can be completely responsive or unresponsive to changes in price.