I’ve been receiving an inordinate number of spam emails lately, which contain mostly images and very little, if any, text. Of course, this is nothing new, but the phenomenon bears a closer look.

There are two reasons a spammer will send a spam message with images. First, the image may give them an opportunity to attempt to circumvent the spam filter. For example, while a spam filter is likely to pick up on the words “cheap Viagra” as a spam message and send it to the junk bin, the same filter may not pick up on the fact that the spammer has sent an image, which does not contain the actual text, but just a .jpeg image of the text.

The second reason a spammer will use images in an email is that they may contain a Web beacon–a tiny, hidden device that sends a message back to the spammer. This beacon will let the spammer know that you have opened the email, and that the address they sent it to is legitimate. As a result, you will find yourself on hundreds of other spam lists.

A ZDNet article today suggests blocking all HTML email completely, and this can indeed be done fairly easily based on the settings in your email client. But speaking as someone who creates and receives a lot of HTML email newsletters that are quite legitimate, there are plenty of people that wouldn’t want to go this route. That an email uses HTML is not necessarily an indicator that the email is spam, as the writer suggests. In fact, almost any type of commercially-produced email is HTML-based.

However, blocking images is worthwhile and will handily address the problem without having to throw the baby out with the bathwater. In most email clients there is an easy way to do this by opting to block images and other external content in HTML e-mail. If you trust the email sender, you can just click a dialog button and see the images along with the text. This eliminates the image problem, while still allowing you to receive your HTML newsletters and other graphically-rich email.