Retargeting

Retargeting shows ads to people who already interacted with your brand — visited your site, opened your app, or engaged with previous content.

"Retargeting" and "remarketing" are used interchangeably by most marketers, though Google historically used "remarketing" for its own product name. Functionally they mean the same thing: showing ads to a warm audience instead of a cold one.

Retargeting typically shows a strong ROAS because it's advertising to people already close to converting — which is exactly why its incremental value is often lower than its attributed ROAS suggests. A meaningful share of retargeted converters would have come back and bought anyway; the ad just claimed credit for a sale that was already likely to happen.