This is the eighth post in a series debunking some common misunderstandings about online privacy. The images used in these posts have been adapted from a tutorial given by Gerald Friedland at ACM Multimedia in Nara, Japan in October. Read previous posts: one, two, three, four, five, six, seven.

Remember that when you post something, it can be found later. While current technology might not be sufficient for someone to identify you by using face recognition software, it's very likely that software coming out in the future would have no problem identifying you (or someone else) based on, for example, a blurry photograph. The same goes for speaker identification software and other technology that can be used to identify people. As time goes on, the technology improves, so never assume that because something isn't possible today, it won't be possible in the future.

In addition, privacy policies for social networks change frequently, so you really don't have control over who can view your posts. Laws governing what must be kept private also change, and vary based on what country, state, or even county you live in, as do company policies - which means that information that must be kept private today might be legal to share in the future.