Hello @PamG035 ,
Opens are when a contact opens an email you've sent them. This is tracked by a 1x1 pixel invisible image being downloaded / shown in the email at the time of opening.
For more info on Open reporting
Clicks are when a contact explicitly clicks a link in your email. These are tracked by the original links you insert being automatically rewritten, with tracking coding at the time of sending. When a contact clicks the link the tracking coding will redirect them to the actual link, while it reports back to our system.
For more info on Click reporting
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