Remarketing is basically a digital marketing strategy in which the target is to re-engage with the users who were previously engaged with the business website either as users or those who abandoned their cart, now the task is to re-engage with those users through advertisements, messages, or both. The main motive of Remarketing is to increase sales by engaging with loyal customers.
To get more deeper knowledge on the topic follow the link mentioned.
https://www.algosaga.com/blog/how-to-optimize-a-remarketing-campaign-that-delivers/