email notifications

Email tracking or email tracker is a method for monitoring whether the email message is read by the intended recipient. Most tracking technologies use some form of digitally time-stamped record to reveal the exact time and date when an email is received or opened, as well as the IP address of the recipient.
Email tracking is useful when the sender wants to know whether the intended recipient actually received the email or clicked the links. However, due to the nature of the technology, email tracking cannot be considered an absolutely accurate indicator that a message was opened or read by the recipient.
Most email marketing software provides tracking features, sometimes in aggregate (e.g., click-through rate), and sometimes on an individual basis.

View More On Wikipedia.org