I was recently looking for pey-per-lead offers to promote in my afilliate programs list when I found out one which was paying nice but had this condition: What does that mean?
When the users registers AND confirms their email. From wiki: The term double opt-in was coined by marketers in the late 90s to differentiate it from what they call single opt-in, where a new subscriber to an e-mail list gets a confirmation e-mail telling them they will begin to receive e-mails if they take no action. This is compared to double opt-in where the new subscriber must respond to the confirmation e-mail to be added to the list. Hope that helps