Demand-side platforms (DSPs) are systems that enable the advertisers to take control of all the ad exchange work via a single interface. DSP enables marketers to manage all of their ad space bids and the pricing for the data, which they are using to target their audience. Similarly to the Paid Search, using a DSP allows the advertiser to manage their ad bids and use performance indicators, such as effective CPA or effective CPC. Because of the things mentioned above, demand-side platforms are often used as retargeting tools. These systems have proved themselves in being able to recognize ad calls in a big inventory volume.