Every ad impression is a data-driven decision made in milliseconds within a fast-paced programmatic ecosystem. Demystifying Signals unpacks the foundational elements that make those decisions possible: the signals flowing through the bid stream. From publisher metadata and device information to audience identifiers and performance insights, this visual guide, developed with IAB Canada’s Programmatic Committee, clarifies where signals originate, how they’re used across teams, and what challenges the industry faces in managing them effectively.