Image: Teens in limousine © IT Stock Free, PictureQuest

Stories of people's online photos being used for nefarious purposes abound: A mother in Florida discovered that a photo she posted of her 5-year-old on Facebook was used to create a new profile, unbeknownst to her. After a soldier's MySpace profile was compromised, a scam artist used a stolen photo in creating a fake Match.com account; he then used the dating site contact to con one woman out of thousands of dollars by posing as a soldier. One blogger found her family's photo being used as an advertisement in the Czech Republic. Another mother's 4-year-old daughter's photo was pulled off of Flickr and posted on a Brazilian social networking site, where it was rated for "sexiness."

The convenience of sharing photos with friends through social networking sites and blogs is undeniable. Unfortunately, so are the dangers. Not only can photos be stolen and used by strangers, but many photos, especially those taken by phones or devices with GPS technology, contain tags that reveal to savvy viewers exactly where the images were snapped. In other words, if a parent takes a photo of their child playing at home and then posts it online, it's possible for strangers to know exactly where they live.

A few simple steps can dramatically reduce your chances of falling victim, and there's no need to give up photo-sharing altogether. Here are seven steps everyone should take to protect themselves and their families when posting photos online:

1. Check your privacy settings. Facebook and many other social networking sites give users options when it comes to who can view their photos and personal information. On Facebook, users can specify that they want only their "friends" to view their photos, or friends of friends, or everyone. (To check your settings, log in to your account and go to "privacy settings.")

2. Make sure you know who your friends are. If you have hundreds of friends on Facebook, chances are you don't know all of them well. Take a moment to review your friends list to make sure everyone still sounds familiar. Perhaps you accepted a friend request from an old high school classmate, but he or she appears to have grown up into an odd person. You might want to consider unfriending him or her.

3. Disable the GPS technology before taking photos with a smartphone if you plan to post the photos online. Even regular cameras are starting to get this technology, so check what information is included on your photos before posting them online. You should be able to turn off the high-tech feature before snapping, and you might want to consider doing so when you are in your home or places you frequent often.

4. Watch out for lower-tech ways of sharing personal information, too. A photo taken in front of your home could reveal your address, or a T-shirt could contain a school logo. If you're posting photos on a blog or other publicly accessible site, you probably want to keep your personal details under cover.

5. Don't post photos that could embarrass your children, even in 10 or 20 years. That means naked bath photos or toilet photos are out, for example. Joanne Villani, the founder of ProtectedPix, which offers a private photo-sharing service, says with facial recognition technology on the rise, it's possible that photos posted now will still be searchable online by the time your now-toddler looks for his first job. You don't want to leave a trail of photographs that could hurt his reputation later.

6. Stand up for yourself (and your child). If a friend or relative posts photos of your child on Facebook and you don't want the images online, ask the poster to take them down. After all, you don't know how carefully others monitor their friends lists, so it's impossible to know who is viewing the photos. The same goes for YouTube, Picasa and other media-sharing sites.

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7. Use a watermark. Bloggers are increasingly turning to watermarks, which imprint their photos with their name or blog title, making it harder for someone to misappropriate the image. Villani suggests adding it in a spot where it cannot be easily cropped out. Doing so, she says, is sort of like locking your door or having a security system: It makes it more likely that a scam artist will leave your photo alone and move on to the next, more vulnerable victim.

The bottom line: It's hard to control how your photos are used once they are posted online, but these steps can reduce your chances of becoming a victim of identify thieves or other types of criminals.

This article was reported by Kimberly Palmer for U.S. News & World Report.