With the development of digital technology images have become an important source of communication and are used all over the internet, as evidence or to depict a scene.However easy to use and freely available image tampering software tools have put a question mark on the credibility of images. Thus it has become mandatory to authenticate the images before they are put to use. This book gives a brief review about the authentication of images against common forgeries like copy-move, splicing and retouching using blind techniques. A comparison of the state of art techniques is also given in a tabular form for easy understanding.