In the reporting tab, there are multiple stats that are display including open, unique open, and page view. The difference can be found below.
Deliveries: The number of emails that successfully arrived in the recipient's email inbox.
Total Opens: The total number of times a newsletter/email was opened. Includes multiple opens from the same person.
Unique Opens: The number of distinct recipients that opened the email.
Total Views: The total number of times an article or piece of content was clicked and viewed.
Unique Views: The number of distinct recipients that clicked on a content piece. Each recipient is only counted once.
Open rate: The percentage of email recipients that received and opened an email.
Leads: The number of prospective clients that have provided their contact details to receive ongoing communications.