When you look at the eNotice Report for a specific message, you’ll notice two separate statistics for "Click-throughs" and "Unique Click-throughs." Though similar, these offer two different insights into the performance of your eNotice.
"Total click-throughs" is the total number of times that eNotice recipients click on any link in a message that they receive, including multiple clicks on the same link. "Unique click-throughs" are only the first click each individual user makes on each link. Subsequent re-clicks are not counted as "unique." Unique click-throughs, therefore, measures the number of users who click on a link, rather than the overall amount of traffic a link generates.
For example, let's say you send an eNotice with three links: Link A, Link B, and Link C.
One reader opens the email and clicks on Link A twice and Link B once. That will register three click-throughs, but only two unique click-throughs. If the reader later goes back to the email and clicks on Link A again, you will now have four total click-throughs (three As, one B) but still only two unique click-throughs (A and B).
If you send an email with one link to 100 readers and all readers click the link once, you'll have 100 total click-throughs and 100 unique click-throughs. If, however, only one person clicks on the link but clicks it 100 times, you'll have 100 total click-throughs but only 1 unique click-through.
Total versus unique click-throughs can tell you whether the links in your mailing had broad interest, or intense interest among a few individuals (and further analysis of eNotify statistics can tell you which individuals clicked the link).