In this post I will discuss common methods in email marketing systems like Opt out, Double opt-in or confirmed opt-in and Single opt-in or unconfirmed opt-in:
Opt-out: Opt out is a method in email marketing where the subscriber of newsletters has the option to opt out of the subscription at any time. Typically, in an opt out system emails include an “Unsubscribe” link in all the emails which are sent as a blast to the subscribers. When a subscriber wishes that he no longer needs the emails from a particular source all they have to do is to click on the “Unsubscribe” link in the emails and they will be unsubscribed from that mailing list and no future emails will be sent from this list. Nowadays opt out system is used by almost all the email managers and email list hosting companies.
Double opt-in or confirmed opt-in: Double opt-in or confirmed opt-in is a method in email marketing where a conformation message is sent to the subscriber when they sign up for newsletters. To be added to the list they have to click on the link in the confirmation message to verify their subscription request. Double opt-in is an industry standard in email marketing and it helps in stopping unverified email addresses to be added to a mailing list.
Single opt-in or unconfirmed opt-in: Single opt-in or unconfirmed opt-in is a method in email marketing where a subscriber is added instantly and there is no confirmation message sent to him to verify the subscription request. Single opt-in is not recommended as it increases the possibility of sending spam to an unsolicited recipient. For Example, a person adds an email address which is not his own email address to a list. Now, the email address will be added instantly and the newsletters will be sent to this email address. Now, the actual email address owner when he receives the email (as he never subscribed to it) may mark it as spam.