Up until now, we have examined how markets help allocate products or services to customers efficiently. One of the lessons in the earlier case studies and applications was that prices are a very useful tool in facilitating trades between buyers and sellers. In this lesson, we will explore another way that prices can be helpful in markets: in revealing information. At first glance, this role is not that obvious. After all, a price is just a number, so how can it possibly transfer any information? Indeed, who is transferring this information and to whom