Remarketing is reaching out again with ads to people who have already visited a site or app but did not complete an action. It reminds people who already know the brand about it and encourages them to return, which is why it usually converts better and more cheaply than reaching new users. In practice it is used interchangeably with retargeting; its more effective variant is dynamic remarketing, which shows the specific products viewed. (Compare: Ad Retargeting, Dynamic Remarketing)