This document discusses 6 secrets of real-time bidding (RTB) advertising. It notes that by automating and optimizing display advertising trading and serving through RTB, publishers and advertisers can improve return on investment. It also mentions that second-price auctions can be manipulated, cookie data has a short lifetime, major advertisers are integrating directly into the RTB ecosystem, targeting is becoming more sophisticated through various data sources, the RTB ecosystem is highly fragmented, and fraud is a major problem estimated to cost over $1 billion.