What are impressions?
Impressions (also called view-throughs or ad views) are how many times your ad is shown to users. The number of impressions is a rough estimate of the number of times people saw your ad, but it can't tell you exactly how many people saw it or what they thought about it.
How does it work?
An impression is typically defined as each instance of a web page, ad, or content being found and loaded.
This method of measurement is popular because it is easy to track and understand, making it a cost-effective way to determine whether an advertisement is being viewed by users.
However, there is some debate over how impressions should be interpreted. Some experts argue that there is no precise way to count impressions, as a single person could see the same ad multiple times through different page views.
This and other factors can skew total impression numbers, leading advertisers to view them with skepticism. To address this issue, most advertisers and publishers agree on a specific method for counting and reporting impressions.
Some advertisers may even base the success of a campaign on other metrics, such as engagement or how users interact with an ad.