Summary - Engagement

Non-clicking readers	Recipients that opened the message and downloaded images, but did not click on any links. We know that they opened the message because images were downloaded.
Shared	Number of times the social media sharing icons were clicked on, regardless of whether the recipient ended up completing the social media post or not.
Display issues	The number of recipients that clicked on the link to view the Web version of the message. Typically this happens when the user was having issues displaying the message in their email client.
Unsubscribed	The number of recipients that decided to no longer receive emails from you. The fact that they unsubscribed may or may not be directly related to the message.
Complaints	The number of recipients that pressed the "SPAM" button in their email client to indicate that the message was unsolicited.