How to Code HTML Email Newsletters

"HTML email newsletters have come a long way in the five years since this article was first published. HTML email is still a very successful communications medium for both publishers and readers. Publishers can track rates for email opens, forwards, and clickthroughs, and thereby can measure reader interest in products and topics; readers are presented with information that's laid out like a web page, in a way that's more visually appealing, and much easier to scan and navigate, than plain text email."

http://www.sitepoint.com/article/code-html-email-newsletters