HTML vs Plain Text Emails
What's the difference between HTML and plain text email?
HTML emails let you view images, graphics and links within the email. Plain text emails contain only words, with no images, graphics or links.
Please note that not everyone has an HTML capable email client i.e. Microsoft Outlook or Outlook Express - therefore if in doubt you should select Plain Text for your email format.
Also if you have problems reading emails from Southwest Sound & Light you may want to change your email format to plain text as they are less likely to be picked up by spam filters and they also take up less bandwidth.