Programmatic advertising
Buying digital ad space through automated auctions in real time, impression by impression, rather than by negotiated insertion orders. Most display and a growing share of video, audio and DOOH trade this way; the efficiency is real and so are the transparency and fraud questions that come with a long supply chain.
Where it's used
Used for display, video, audio and connected TV at scale. Good for reaching audiences across many sites, but it needs site lists and supply-path checks.
Example
Under a second
Illustrative scenarioYou open a news article. Before the page finishes loading, the publisher offers that impression to an exchange, dozens of advertisers' systems bid based on context and audience data, and the winner's ad appears. Every step in that chain can take a slice of the money, which is why advertisers audit where each dollar goes.