impressions
The number of times an ad is displayed, whether or not anyone interacts with it.
Definition
An impression is counted each time an ad is loaded or shown to a user. It differs from reach, which counts unique people, because the same person can see an ad several times. Definitions vary between platforms, for example in how long an ad must be on screen to count, so ask how each source measures it. Impressions suit awareness objectives but do not prove attention or action. Request viewability and invalid-traffic information with impression counts, because these show how many were actually seen by real people.
In a sentence
The campaign delivered millions of impressions across the network, according to the platform's report.
Impressions count repeat views, while reach counts unique people.
