Impression, sometimes called a view or an ad view, is a term that refers to the point in which an ad is viewed once by a person, or displayed once on an outdoor unit or OOH display. The number of impressions of a particular advertisement is a term used to describe how many people have been exposed (or had the opportunity to be exposed) to your advertisement in a given period of time. For example, assume there is a room of five people watching a digital screen and your ad displays one time. Therefore, it had a total opportunity to have made 5 impressions. If your ad displays again, it will have had a total opportunity to have made 10 impressions. Unless specified as in-market, impressions include all persons who notice the ad unit, regardless of the origin of their trips. Impressions are reported in weekly increments. Also known as Eyes on Impressions (EOIs).
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