An electronic magazine, whether delivered via a Web site or an email newsletter.
Ezines range greatly in size and scope, from irregular newsletters reaching a handful of subscribers to daily journals reaching hundreds of thousands of subscribers.
Some ezines are strictly non-profit. Some are extremely profitable. Other would be for-profit if they could attract the necessary audience and advertisers.
see also: Email Marketing Tools
Udemy: Email Marketing – learn email marketing with online courses.
EzineArticles.com – ezine article submission service