RTB (Real Time Bidding) is a part of the general term „Programmatic Buying“. Programmatic Buying is defined as any form of inventory buying based on the use of demand side technology. It describes display advertising that is aggregated, booked, flighted, analysed and/or optimized with the help of algorithms. That includes RTB but also non-RTB methods. RTB can be understood as the capability to bid different prices for each impression based on the information available for this impression.