Several attributes account for the rise of email as a marketing tool:

Faster Prep Time

Depending on the campaign creation tools that you use, email marketing programs can be quick to create and may arrive in the customer's inbox immediately.

More Flexibility

It is much easier and less expensive to create multiple offers and test various creative and copy schemes in email than in traditional ?snail mail."

Reduced CPM

Email messages cost only a few cents per recipient compared to traditional direct mail costs because email campaigns don't incur printing or postage costs. Email costs range from $.01 to $0.25 for per message, compared about $1.70 to $2.00 for each item mailed in traditional direct snail mail.

Greater Acceptance

Some 73 percent of U.S. consumers say they prefer email as their method of contact with online merchants. (Virtually the same percentage also say they prefer rich-content media email ? with graphics and typography ? versus plain-text email.

Quick Response

Responses from recipients usually arrive within 48 hours rather than taking days or weeks via printed and posted mail.

Higher Response Rates

It is easier and more inviting for someone to respond to an email message than to pick up the phone or mail a response card. And email has a much higher average click-through rates (between 5-15%) than online banner ads.

Accurate Reporting

Electronic forms of delivery and response make tracking and reporting fast and easy. It is much easier than waiting weeks for responses and returns.
Email marketing can use a variety of tactics ? including offers, coupons, contests, newsletters and other value-added links and information.

Those tactics can basically be divided into two types ? permission-based marketing and spam.
Spam is the electronic equivalent of junk mail or that annoying telemarketing call during dinner. It is unsolicited and unwanted. Unfortunately for consumers, today spam represents 10% of all email.

In response to this invasion, email users have created inbox filters and dummy email addresses.
Permission emails are those messages that users have requested. This can take the form of newsletters, or a checkbox in the registration process on various Web sites giving the marketer permission to deliver product updates or other marketing information.

Forrester Research predicts that the number of solicited emails will grow to 250 billion in 2002. Permission emails have higher success rates than spam ? both in terms of ROI and in preserving a company's reputation.

Permission email can take the form of acquisition or retention email ? that is, mailings whose primary objective is to prospect for customers or whose objective is to forge a relationship with an existing customer base. In 2000, some 57 percent of permission email dollars were spent on retention and 43 percent on customer acquisition.