Every digital image is encoded with digital information, EXIF, aside from the actual picture. That information holds interesting data: When the picture was taken, if it was modified and when it was last modified, Camera information, focal length, Camera make and model among other information.

A geotag allows you to identify the location where the image was taken using longitude and latidude based coordinates. This can be determined from the camera, external GPS device or embedded later. This gives you a new way to sort and search through your photos.


In Picasa via Cnet(Click title for full article)

After downloading your photos into Picasa, it’s simply a matter of clicking on the tools tab and selecting the ‘Geotag with Google Earth’ option. This opens the mapping application in which you navigate to the place where the photo was taken. A single click then embeds the relevant latitude and longitude details into the photo’s EXIF metadata file.

In iPhoto

Select the photo or album then hit the “i” icon on the lower right corner of the screen to edit the photo/albums information. At the bottom of the panel you will see places. Type in the name of the place the photos were taken.