Steganography consists of hiding a secret message within another message. Unlike cryptography, steganography tries to achieve security through obscurity, hiding the very presence of the message. Ideally, the steganographic message will look identically to a normal message.
This talk examines different techniques to hide messages using steganography from the perspective of a PHP developer. From more classical techniques such as hiding an image within another image using the least significant bits of each pixel, to more advanced ones like using TCP/IP packets.