Practical explanation:
Most people who visit a website for the first time don't take action. Remarketing lets you follow up by showing ads to those same people as they continue browsing elsewhere — on Google, YouTube, Gmail, or other sites in the display network.
How it works
Remarketing uses a pixel or tracking tag to identify visitors and group them into audiences based on what they did on your site. Those audiences are then targeted with ads on other platforms. The more specific the audience — for example, people who visited a pricing page versus people who just landed on the homepage — the more relevant the ad can be.
Why it matters
Someone who already visited your site knows who you are. That familiarity typically translates into lower cost per conversion compared to targeting a cold audience.
When to use it
It makes sense once you have enough traffic to build a meaningful audience. It works particularly well alongside search or social campaigns — as a follow-up layer rather than a standalone strategy.
Related terms: Retargeting, Pixel, PPC, Paid Traffic