Alternatively referred to as geocoding, geotagging is the process of attaching a physical location to a photograph's metadata. The geotag may include regional geologic data, such as city and state, or it may include more precise data such as the latitude and longitude. Geotagging data may then be read by programs to show the user where the photo was taken.
Geotagging is especially prolific online. For example, when it is used on Flickr, photos may be linked to a specific location, allowing anyone to view images taken in that part of the world.
Today, there are legitimate privacy concerns regarding geotagging. In some cases, users uploading photos to social media sites are unaware that their photos have geotagging data associated with them. Geotagged photos allows the public to know exactly where you have been or where you are now, which can then lead to concerns around cyberstalking. It could also mean a thief would know when you are away from your house.