St. Louis (KSDK) - Think of all the photos you share through e-mail or by posting to a website. Pictures from your house, your kids at school or images from the road. Wherever you are when you snap those pictures, you might be pinpointing your exact location to strangers. It's called geotagging.
Lisa Martin, who we found taking pictures of the Gateway Arch with her iPhone, thinks she's heard of geotagging.
"Something to do with mapping, coordinate mapping," said Martin.
But her friend has a better grasp of the concept.
"I think it's something like you put your pictures on the internet and people can see where you're at," said Mona Dheer.
Geotagging involves location information embedded in the photos you take from GPS-equipped smart phones, but also on some digital cameras. In some cases, the latitude and longitude of an e-mailed or posted photo can be found with a right click on the property section of the picture.
"Oh wow, I didn't know that," said Martin. "Oh, not safe at all."
Larry McClain, an investigator with the Missouri Internet Crimes Against Children Task Force, doesn't blame her. The detective has not had a geotagging case come across his desk yet.
"But it is a concern," he said.
McClain believes many people aren't aware of the information they may be inadvertently sharing when they post images on the internet; information that could be good for bad people.
"If you're a person that takes a lot of photographs or posts a lot of information, I could pretty much tell you when you leave your house, where you're going to breakfast or where you work at, what time of the day you come home, what school you go to," said McClain.
Facebook and others block locations from photo posts, but at least one website believes it's a big enough problem to warrant raising awareness.
"icanstalku.com" pinpoints Twitter-poster's locations based on pictures they tweet. It also offers instructions on how to disable geotagging on various smartphones.
St. Louisan John MacEnulty is a shutterbug. He says he is aware of geotagging and allows it on some pictures. But he blocks it in other cases like on photos taken from home.
"You just want to try and avoid, you know, taking pictures like, you know, hey here's my brand new hi-def TV, you know, but we're going to be going on vacation for the next month. Bye," joked MacEnulty.
McClain says the key is to know your equipment and the websites you use and decide your comfort level.
"Do I want everyone to know exactly where I'm at?" said McClain.
Photo sharing websites may give you the option to block the locations on your pictures in the privacy section. For step-by-step instructions on how to disable the geotagging on your smartphone visit icanstalku.com.