Images on the Web

Did you now that pictures that you post on the internet dont belong to you after its posted? Well I dont think its right for other people can take YOUR images that are on the web like on facebook. Like if i went to the mall and saw a picture of me and my family i would be mad because its our privacy not theirs.  I heard that this girl posted a picture of her family on her blog and saw it in a store. This is what i think and heard about the internet owning your images.