App: What do different Contact statuses mean?

New = Contact has not yet Opted-In: did not click on the opt-in link in the email

Viewed = means the contact viewed a resource, but has not yet opted-in

Opted-in = contact has opted-in to a campaign: receiving the emails from campaign

Opted-in & Viewed = means the contact has viewed a resource, and Opted-in

Unsubscribed = contact clicks the unsubscribe button and will not receive emails from you again.

Bounced = contact did not receive the email, most likely due to bad email address.

Released = the contact has been added as a contact by another user and assigned to a campaign

To know more about different contact statuses, please check this link: Web: What do different Email or Contact statuses mean?