What defines the total number of times an advertisement is displayed to a user?

The total number of times an advertisement is displayed to a user is appropriately defined by impressions. Impressions refer to each instance an ad is presented on a web page, regardless of whether the user engages with it or not. This metric helps advertisers understand how often their ads are being seen across various platforms and can be critical for gauging the effectiveness of an advertising campaign.

Unlike visibility metrics, which may focus on how prominently ads are displayed, or reach figures that indicate the unique number of users who see an ad, impressions count each occurrence of the ad. Ad exposure rate might relate to frequency or the percentage of the target audience that has seen the ad, but it does not capture the total count of displays. Therefore, impressions are the most accurate measure for defining how often an advertisement appears to a user.