Ad Exchange is a platform that relies on RTB to determine the rates for the inventory that the publisher is willing to sell. Such a platform helps media buyers and sellers to interact and establish a transparent environment to fulfill the transactions. Media sellers can sell their inventory and potentially enter more auctions from one source for each dollar spent. Media buyers, in their turn, can gain access to a much larger number of partners. Moreover, it is possible to access mass audiences and use various targeting tools that help increase the efficiency of advertising campaigns.