(Also called a View) A single display of online content to a user’s web-enabled device. Many websites sell advertising space by the number of impressions displayed to users. An online advertisement impression is a single appearance of an advertisement on a web page. Each time an advertisement loads onto a users screen, the ad server may count that loading as one impression. However, the ad server may be programmed to exclude from the count certain non-qualifying activity such as a reload, internal user actions, and other events that the advertiser and ad serving company agreed to not count.