Some of the terms or keywords that can be found in reporting are defined as follows:
Hard Bounces / Permanent Failure - Permanent failures when trying to deliver to an address. This means that the address either no longer exists or never existed. Hard bounces we will only try to deliver once since we received a permanent failure with the system. Our system knows it could never be delivered to that address. A usual bounce message for a hard bounce reads "Recipient does not exist."
Impression - A view of the content that resulted from it being shared on a social network. The email address associated with an impression is that of the sharer, not the viewer. An impression is only recorded when you've included Social Share links in your content.
Soft Bounces / Transient Failure - Temporary failures when trying to deliver to an address. This could be someone who is out of the office, has a full mailbox, or the server may be busy when trying to deliver the mailing. Soft bounces we will try multiple times to get delivered to an address.
Total Clicks / Clicked - This works the exact same as Total opens/Unique opens but instead it measures how many times a link(s) is clicked.
Total Opens / Opened - This measures how many people have opened your mailing in total. It counts all the opens even if a recipient opened it more than once
Unique Clicks - This registers only the first time a recipient clicks a link(s). Any other times they click the link will not count towards unique clicks.
Unique Opens - A unique open is counting the recipient's FIRST open and does not include any subsequent opens. For example, if you sent a mailing to 10 people and all 10 people opened it, it would register 10 unique opens. If one of the recipients opened it 3 times, it would still be 10 unique opens but 12 total opens(the first is unique and then the other 2 count towards the total opens)
An unique open is determined by a tracking image being loaded -OR- by a clickthrough being recorded, whichever comes first (because even if the recipient has images disabled in their email client, if they clicked a link, we know they opened the message).