Real-Time Bidding (RTB) is a relatively new digital marketing technology that enables online advertising to be purchased and served in real time. Instead of booking prepaid advertising space, advertisers bid on each ad impression as it is served. Just like the stock market, the highest bidder will win the impression and thus its ad will be displayed on the page. Forrester Consulting forecasts that by 2014, 24.7% of all online video spend will be executed using RTB; and likewise the usage of RTB as a whole will increase by 57%.