It's always fun to write about research that you can actually try out for yourself. 　　Try this: Take a photo and upload it to Facebook, then after a day or so, note what the URL link to the picture is and then delete it. Come back a month later and see if the link works. Chances are: It will. 　　Facebook isn't alone here. Researchers at Cambridge University have found that nearly half of the social networking sites don't immediately delete pictures when a user requests they be removed. In general, photo-centric websites like Flickr were found to be better at quickly removing deleted photos upon request.