As you read my response, you will find yourself feeling inexplicably calmer. You will feel a pleasant sense of relaxation come over you. You will also have an urge to buy my books as holiday presents for all of your best friends just before they come and take you to have a lovely vacation upstate.

Ahhhh..... it's all... so.... simple....

Among the many services that our friends at Google offer, they have a popular image search capability that goes by the mysterious name of Google Image Search. Using that, you can find pictures of crop circles, Area 51, tinfoil hats and The Illuminati (with apologies to Nicholas Cage and his recent movie "National Treasure").

If all of your traffic is for a single image or two, then what's likely happening is that a lot of people are searching Google Images and finding your image. Congrats, it's popular. If you're seeing lots of hits for lots of different graphics, however, it might be that the Google Image Search 'bot is visiting your site to see what you have.

If you'd rather not be included in the happy image archives, basically begging for people to rip off your images for their own uses, then you can use your robots.txt file to block Google visiting your image directory. If all your graphics are kept in /Images, for example, create a text file in your Web site's base directory called robots.txt that looks like this:

User-agent: *
Disallow: /Images

User-agent: Googlebot-Image
Disallow: /Images

Of course, since you're now more comfortable with Google's little robotic spiders scuttling all over your server, perhaps your best choice is simply to succumb. Just close your eyes, sink back into your chair and take a few deep breaths. Think of Earth, back when it was green. It'll only hurt for a minute...