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Email Promotions versus Email Newsletters
http://cdemails.com/articles/7240/1/Email-Promotions-versus-Email-Newsletters/Page1.html
DM Pulse
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By DM Pulse
Published on 12/9/2009
 
When many people think of "email marketing," they think of opt-in email promotions. That is, where you buy a product online and click on the check box for "send me periodic mailings with news of related products and services from XYZ, Inc." Then, once a month, you get a short promotional email.

This is a very common model of email marketing, and it has proven itself to be one of the most effective digital marketing techniques. The problem arises when you take this model of email marketing and apply it to email newsletters.