Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. The word steganography combines the Greek words steganos (στεγανός), meaning "covered, concealed, or protected", and graphein (γράφειν) meaning "writing". The advantage of steganography over cryptography alone is that the intended secret message does not attract attention to itself as an object of scrutiny.
The Steganography tool used to encode secret messages inside images and to decode them again. It uses an algorithm to convert the given message into appropriate binary data which then will be hidden in the alpha channel of the given cover image. To decode a message from a given image, a similiar algorithm is applied on the image data.