Reference / Glossary / Infrastructure and standards
Ad Server
The system that stores creative, decides which ad to show for a given request, serves it, and records the impression and click. Publishers run a sell-side ad server (Google Ad Manager dominates); advertisers run a third-party ad server (Google Campaign Manager 360, Flashtalking, Innovid) to serve creative consistently across publishers and to hold an independent count for reconciliation.
Related terms
Cite this entry:
Agency Echelon. "Ad Server." Agency Echelon Reference, reviewed September 2026. https://agencyechelon.com/reference/glossary/ad-server/