Search Ads 360 overview
A remarketing target is created when you apply a Google Ads remarketing list to a Google Ads manual campaign, Shopping campaign, or ad group.
A campaign or ad group remarketing target is used to display different ads or to bid differently to reach customers who have previously visited your site.
A Google Ads remarketing list can be applied to a Google Ads campaign or ad group for negative remarketing as well. That is, to exclude the members of list from receiving additional ads.