How do ads work that are based on visits to advertiser websites?
In addition to ads based on interest categories, Google and YouTube also allow advertisers to show you ads based on your previous interactions with them, such as visits to their websites. For example, someone who visited the website of an online sporting goods store can receive ads about special offers from that store. Advertisers cannot use this technology to identify you personally, but it enables them to deliver much more relevant ads to groups of users who previously came to their website. If you prefer not to receive such ads, you can opt out by clicking the “Opt out” button on the homepage of the Ads Preferences Manager.
