(MCT) — A life-size picture of Danielle Smith's family is displayed in a Czech Republic grocery store, advertising its quick home delivery service.

Smith, a mommy blogger who lives in O'Fallon, Mo., had never heard of the store and had no clue her family had become their unwitting endorsers. She was alerted by an old college friend she had recently found on Facebook, who had since moved to Prague. He happened to walk by the store and recognized the photo from her profile page.

A week and a half ago, he took a picture and sent a snapshot.

Smith was stunned. She had posted the family picture on her site, ExtraordinaryMommy.com, Facebook and a few other social networking sites. She never imagined it would have been appropriated for an ad 5,000 miles away.

"It felt a little bit creepy to me," she said. She hasn't decided yet what to do about it, but the story itself has created a stir on her site and skyrocketed traffic to 180,000 hits in four days.

Smith says she has learned not to put hi-resolution images online. But, her story does speak our changed expectations of personal privacy. Do you expect that once you post a photo online that it's fair game for anyone to use?

Tens of millions of photographs are posted online and rarely is any harm done. But, you always have to think before you upload, especially images of your children and or photos that give obvious clues about where you live.

Stephen Balkam, CEO of the Family Online Safety Institute in D.C., suggests that parents always use the privacy setting on social networking sites such as Facebook, which allow you control who sees your pictures.

Think twice about posting a picture if it shows a revealing body part (no matter how innocent) or reveals your location. Kimberely Isbell, a fellow at the Berkman Center for Internet and Society at Harvard University, offers these additional tips:

Only post low-resolutions pictures, which do not enlarge well, or include a digital watermark on your photos.

Consider licensing through Creative Commons.org, where you can specify whether a photo can be used for commercial purposes. You can note that if a photo is reused, it must be attributed to you.

Flickr has a mechanism that prevents an image from being copied. Although most hackers can crack this type of software, it will deter those looking for an easy image to grab.

Learn how to use Flash to imbed your photos in a blog, rather than using jpeg images. It's harder to copy images from Flash.

Create a very unique file name for the photos you post, and you can periodically search Google images for those file names.

"Anything you can do to make it harder to copy the photo," will deter the majority of those likely to swipe a photo, she said.