Impression

This term describes the successful access of one ad creative, regardless of whether it is seen or not. You may generate multiple impressions with a single pageview, in accordance to how many graphical ads are featured on that page. For example, if a page contains 2 banners and 3 buttons, and it loads completely, your one pageview will account for 5 impressions.

Advertisers and publishers often negotiate deals based on how many ad impressions will be delivered at a given CPM rate. As with all other CPM-based media buys, though, advertisers are never assured that their ads will be seen by 100% of the people who visit a page. If, for example, visitors are avoid an ad by scrolling or clicking elsewhere before the graphic has loaded, it may still count as a delivered impression.

Impressions may be tracked using log files or ad serving software.