'Well, it depends on what you mean as “own.” Under copyright law, unless there is an agreement to the contrary or the photograph or video is shot as part of your job, a copyright to a photograph generally belongs to the creator. As the copyright owner, you own the exclusive rights to display, copy, use, produce, distribute and perform your creation as you see fit and approve. As the subject of the photograph, you have a right to publicity, which allows you to get paid for the commercial use of your name, likeness or voice.
But what happens when you decide to post that picture on the Internet — perhaps on Facebook or Twitter (using Twitpic), or some other social network or photo-sharing site?
You may be shocked to find out that once you post on these sites, that although you still “own” the photograph, you grant the social media sites a license to use your photograph anyway they see fit for free AND you grant them the right to let others use you picture as well! This means that not only can Twitter, Twitpic and Facebook make money from the photograph or video (otherwise, a copyright violation), but these sites are making commercial gain by licensing these images, which contains the likeness of the person in the photo or video (otherwise, a violation of their “rights of publicity”).'
You can read a legal perspective on this here.