The RTB or Real Time Bidding is a system to bid for an ad-impression on a real time. RTB is similar to a financial market. It enables advertising inventory to be bought and sold on a per-impression basis via programmatic instantaneous auction. A buyer or advertiser can use the RTB technologies to bid higher or lower value for a specific ad impression depending upon how attractive the impression or the audience is for its business. The RTB ecosystems put significant emphasis on user information (geographic, demographic, behavioural data, for example), and the publisher data (the publisher domain, context etc.).