Impressions on Pinterest refer to the number of times your content, such as Pins or ads, was on screen. This means that someone saw your Pin, whether it was in their feed, search results, or category page. Impressions are an important metric to track because they provide an overview of how many people have potentially seen your content, which can help you measure the overall reach of your Pins. However, its important to note that being shown doesnt necessarily mean being seen, so its also important to track other metrics such as engagements and link clicks to understand how your content is performing.

In summary, impressions on Pinterest are a measure of how many times your content was on screen, and they are an important metric to track to understand the overall reach of your Pins.