An e-zine is an online magazine. Most of the e-zines today are targeted toward Internet distribution and are meant to promote websites.
Normally, an e-zine caters to a particular niche or topic. It could be anything from "how to make money online" to "how to train your pet". E-zines are distributed to their subscribers normally through email. People send e-zines to be published on a consistent, preplanned basis. For example, an email will be sent out every day, every three days, weekly, biweekly, or monthly.
These e-zines are distributed using an autoresponder. An autoresponder is programmed for every subscriber to receive the emails in a chronological format and in a sequential order. This is the biggest difference between an e-zine and its offline counterpart. An e-zine can send previous issues anytime regardless of when the subscriber has opted in to the e-zine. The autoresponder will do its job of follow-up from the day the subscriber has opted in and will follow through until its run is exhausted.