Many small businesses find direct e-mail marketing a cost effective marketing tool. Email communication is often more effective than printed direct mail, because a reader can click on a link and go straight to the company's website.
Direct e-mail marketing is about sending permission-based opt-in e-mail, rather than unsolicited commercial e-mail (UCE).
Permission-based opt-in e-mail is a term for a promotional e-mail that recipients have previously requested by signing up at a company's website or ad. So opt-in e-mails are only sent to people who specifically request them.
UCE or unsolicited commercial e-mail, also called spam, is a term used to describe an electronic promotional message sent to a recepient without his prior request or consent.
Direct marketing e-mails often include mechanisms that provide the company with feedback on the effectiveness of a campaign, by making it possible to track metrics such as the number of e-mails that were opened, the number of clicks that were generated from an e-mail, the number of recipients that requested removal from the company's list, the number of e-mails that were bounced by the recipient's server etc. | 
