Through HTML, email can be improved stylistically by photos, graphics and text styling. But many people use email clients that automatically take out photos, graphics and styling, or use mobile devices that show text-only versions by default. A good email campaign should thus produce an HTML version of the email blast and a text-only version.

The text should be able to stand on its own. Photos and graphics should be complementary rather than necessary, since many people won't be able to see them. An email message should look good even when images are blocked and show up as empty boxes. Photos and graphics shouldn't take up so much space that the viewer must scroll through to get around them. If photos or graphics interfere with a quick intake of an email's main idea, then they shouldn't be there.

A good guide is to keep text and graphics at an 80:20 ratio.

For additional information and resources, check these out:

• http://newsletter.blizzardinternet.com/email-marketing-why-text-is-key-to-html-newsletters/2008/07/22/
• http://www.campaignmonitor.com/blog/post/1987/html-email-design-guidelines-for-2006/
• http://www.newsweaver.co.uk/designandcontent.php