Steganography: Hides a message within another message and looks like a normal graphic, video, or sound file. Cryptography: The message is encrypted; looks like a meaningless jumble of characters.
Steganography: A collection of graphic images, video files, or sound files on a disk may not look suspicious. Cryptography: A collection of random characters on a disk may look suspicious.
Steganography: A smart eavesdropper can detect something suspicious from a sudden change of message format (i.e., text to graphic images). Cryptography: A smart eavesdropper can detect a secret communication from a message that has been cryptographically encoded.
Steganography: Requires caution when reusing pictures or sound files. Cryptography: Requires caution when reusing keys.
Steganography: There are no laws associated with steganography. Cryptography: There are some laws that ban cryptography.