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Impression - Impressions are the number of times your content is displayed, no matter if it was clicked or not.
View - Views are when a viewer watches 30 seconds of your video (or the full duration of the video if it's shorter than 30 seconds) or interacts with your video, whichever comes first. View rate is similar to click-through rate (CTR), but instead of measuring clicks, it counts people who viewed your video ad after seeing it on YouTube. You can use View rate to track the value of your video campaigns on YouTube.
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