An Ad Exchange is a digital marketplace where advertisers and publishers can buy and sell advertising space in real-time. It connects various parties, including advertisers, publishers, and demand-side platforms (DSPs), allowing them to bid on ad inventory. This process helps ensure that the right ads reach the right audience at the right time. Through an Ad Exchange, advertisers can access a wide range of websites and apps, while publishers can maximize their revenue by selling their ad space to the highest bidder. This automated system streamlines the buying and selling of ads, making it more efficient for everyone involved.