Image Safe allows you to protect your images form being easily copied off your website. It will stop users from being able to drag images out of the web browser or use contextual menus to save images off your site.
*Try to drag the above images out of your web browser. I bet you can only get one!
NOTE: No image is 100% safe on the web. Anyone with knowledge of digging through website code will be able to find the url to an image. Even if its protected with Image Safe. However, Image Safe does protect from the 99.9% of the people that have no clue on how to do that.