Many social networking sites, such as Facebook, place ads on the side of the page. On Facebook, these ads change based on what your friends are doing. Many ads on Facebook feature a “like” button. If you click the button, the ad may then appear on your friends' Facebook pages with a note underneath saying you like the ad. If enough of your friends click “like,” the ad may appear in your main Facebook news feed. Facebook calls this example of targeted advertising an “engagement ad.” Facebook also targets ads by placing ads related to your status. For example, if you update your status from “single” to “engaged,” you may start seeing ads for local jewelers and wedding dresses on your page.