Geotagging embeds the exact location where the photo was taken, within about 15 feet. The feature exists in GPS enabled cameras and almost all smartphones. If you upload those images to the internet, what will they reveal about you? Well, that you have a silly dog, a pretty cat, a charming kid, a new car – and where you live. That?s right, your address is available behind the scenes for anyone knowing how to look for it.

The iPhone and Palm Pre are two smartphones that automatically embed the user?s latitude and longitude in each photo?s metadata. That?s data about data – information hidden in a file that is not readily visible. In jpeg images, you might find the ISO setting used when the photo was taken, the software used to process it, and where you were when you clicked the shutter.

Let?s say you are on vacation and sending a daily journal to friends. People who scan Twitter posts for locations have already recorded your home address from that cat photo. Your Twitter posts and that photo of you under the Eiffel Tower broadcast clearly that you are not at home. How do you spell B-U-R-G-L-A-R?

You could turn off the geotagging for the camera, but then all locations are disabled. Now, you can?t look for the restaurants in Paris or find the route to the Louvre.

Some Call it Stalking - I Call it Love

I Can Stalk U is a website set up to make camera buffs aware of how much information is available when they post a photo online. You also could be advertising your home address when you are advertising Aunt Milly?s diamond necklace on Craigslist. That glittering jewelry just might catch the eye of a resourceful thief.

I Can Stalk U was started in Massachusetts by Ben Jackson, security analyst for Mayhemic Labs, and Larry Pesce, a senior security consultant at NWM. They also give presentations on their favorite topic at technology conferences. Their website contains frequently updated instructions for disabling the location tracking feature on many smartphones.

Disabling the iPhone is relatively simple, they tell us. Use Settings, General, Location Services. Be aware, though, this disables all your location features. On the PalmPre, go to Location Services also, where you can pick and choose among three disabling features. Changing settings on the Google Android phones will also kill all your location features if you pick the wrong setting. The Blackberries have multiple approaches. For exact instructions with text and pictures go to the "Help Me Fix This" section of Jackson and Pesce?s web site.

More and more social networks are adding Geotagging - if you want to secure your privacy, pay close attention - Facebook is just the latest company in the geottaging game
More and more services are adding Geotagging – if you want to secure your privacy, pay close attention – Facebook is just the latest company in the geottaging game

Facebook?s latest feature, Places, that allows friends to check in on you is more complicated The Electronic Frontier Foundation [EFF] has an entire section on the things to consider before taking advantage of this new feature. Of special concern is that your friends can authorize the disclosure of your location data. Read the ACLU?s (American Civil Liberties Union) DotRight?s write up about Places and how you can try to control its implications and possible invasion of your privacy.

Many features built into our latest technology were originally conceived as a convenience for us all. However, we must be vigilant against the possibility that such good features may be turned against us by unscrupulous individuals or organizations.