Google Remarketing is much different than running a banner based campaign on Google’s Display Network, usually something like that is more of a branding exercise due to the low CTR. Remarketing, however, allows you to show ads to users who've previously visited your website as they browse the Web.
When you use remarketing, you can tag pages of a site that correspond to certain categories you want to promote. For example, you could add a “TV” tag on all of the pages where you sell televisions. You can then create an AdWords campaign to show highly relevant messages (such as ads displaying a special offer on TVs) to people who've visited these pages as they browse sites across the Google Display Network.
Remarketing allows you to communicate with people who've previously visited key pages on a website, allowing for a powerful new way to match the right people with the right message.
When combining keyword campaigns with remarketing, we might see higher conversions for campaigns overall. For example, if you have keywords that you don't use because you haven't seen conversions in the past, you can use these keywords to drive traffic to your site, then use remarketing on the Google Display Network to capture incremental conversions from a more qualified set of potential customers.