Maximize the traffic in any website by giving visitors a chance to come back to that website again. One of the ways to keep them coming back for more is to have them sign up and become members of an opt-in list. An opt-in list refers to a list of the email addresses of people who have given their permission to receive publications from the site owner.
An opt-in list will get visitors hooked to the website because once they are included in that list they will be able to receive publications, offers and other promotional materials of the site. Most websites offer people who sign in their opt-in list a chance to receive newsletters according to their interests.