# Ad impression: what it is and how it works · Zorraquino
> An ad impression records one exposure of an advertisement according to the rules of the system that measures it.
URL: https://www.zorraquino.com/en/dictionary/advertising/impression.html

# Ad impression

An ad impression records one exposure of an advertisement according to the rules of the system that measures it

What it means, how it is used and where it comes up, with its related concepts.

[The whole glossary](https://www.zorraquino.com/en/dictionary)

## What it is and how it works

It differs from reach, which tries to count unique people or accounts. It is worth distinguishing between served impressions, viewable impressions and actual attention. These measures answer different questions and should not be treated as equivalent when evaluating a campaign.

Also known as

Impression

Topics

[Marketing and sales](https://www.zorraquino.com/en/dictionary/category/marketing-y-ventas)

## Related concepts

- [Reach](https://www.zorraquino.com/en/dictionary/digital-marketing/scope.html)
- [A/B test](https://www.zorraquino.com/en/dictionary/digital-marketing/ab-testing.html)
- [Cost per thousand impressions](https://www.zorraquino.com/en/dictionary/advertising/cost-per-mille.html)