Publisher

A publisher is the party that owns or controls the traffic source and runs the offer against it — the supply side of the advertising equation. The term covers everyone from a news site selling banner slots to an affiliate pushing paid social traffic; in affiliate networks 'publisher' and 'affiliate' are frequently used interchangeably for the account that sends traffic.

Media buyers wear the publisher hat inside every network dashboard: your publisher ID is what payouts, caps and quality reviews attach to. On ad networks the word flips to the other side — there, publishers are the sites and apps whose inventory you buy. Knowing which meaning applies in a given conversation prevents genuinely expensive misunderstandings when negotiating deals.