Impression

Impressions are the basis of many advertising prices because they say something about the audience. They are not counted by the player but measured or estimated: from footfall counts, traffic data, sensors or cameras. In programmatic trading, a multiplier is often passed along with an ad play, stating how many impressions it represents. How many people pass a screen depends heavily on the location and the time of day.

An impression is not the same as an ad play and not the same as a glance; the advertising bodies separate several levels, from presence in the area to actual perception. Anyone reporting impressions should state the source and the method, so that offers remain comparable. Measurement with cameras or sensors can have data protection implications; this glossary does not give legal advice.