an amount of something left over when requirements have been met; an excess of production or supply over demand.
Example: The gas prices are so low because there is a surplus of oil.
So....why is it important?
Companies vary greatly in terms of their missions, strategic goals and product offerings, but every business has an underlying goal of generating surplus. Every producer and consumer in an economy wants to gain utility by increasing surplus.
Consumer surplus is the difference between the total amount that consumers are willing and able to pay for a good or service and the total amount that they actually do pay
Producer surplus or producers' surplus is the amount that producers benefit by selling at a market price that is higher than the least that they would be willing to sell for.