With the upcoming release of the next iPhone, many iPhone owners will consider getting a new iPhone and passing on their existing iPhone to someone else; possibly even selling it to someone they don't know. If you are considering this, you'll want to be careful. Your iPhone probably contains a lot of personal data that you would not want released into the wild. If you are getting rid of your iPhone, make sure you remove all of the private data first. You can read how to do so here: http://www.zdziarski.com/papers/wipe.html