A loS.sless (reversible) data hiding (embedding) method inside an image (translating medium) - presented in the present work using L_SB (least significant bit). technique which enables us to translate data using an image (host image), using a secret key, to be undetectable without losing any data or without changing the size and the external scene (visible properties) of the image, the hid-ing data is then can be extracted (without losing) by reversing the encoding process , knowi11g and using
the same secret key. This method tested by using two images a:nd by
u-sing several embedding bit rates the result is that the host image
undlstinguisbable from the st go images , then we used (PSNR) and (MSE) methods to fined the aifference values between the host image and the stego images.