The relationship between the prices of a good or service and the quantities supplied to the market by producers within a given time period, all other things constant.

For example to see how much Coke producers want to sell depends on the price of the Coke. When the price of Coke rises some producers will sell more of it. In general, the quantity of Coke, or of any good or service that producers would want to sell, depends on the price. The higher the price, the more of the good or service suppliers would want to sell; alternatively, the lower the price, the less they want to sell.