its a kind of watermarking to detect tamper and manipulation for the original or important multimedia data. For instance, in case of image fragile watermarking, a fragile watermark is embedded imperceptibly into the host image as a mask. Since this embedded fragile watermark is sensitive to any tamper and easily will be destroyed. Finally in the extraction part shows us which part of the image is tampered. That 's how we can verify the authentication of multimedia data.