Steganography
Today, reading all kind off things after hours, I've found an interesting subject : Steganography. What this term really means : well, it represents a technique of hiding something by changing it's form or by encapsulated it in something else. This way of covering something is used since long ago, from the times of ancient Greeks ( where they used head tattooed slaves to send messages ).But ,steganography have become more known with the introduction of digital photos. Why, because photos permit hiding information very well without any suspicion. So called Digital steganography can be used where cryptography isn't possible or legal. We can easily send coded messages into photos to our Chinese fellows, without any problem. Sadly , digital steganography has a bad part. I can be ( and it was ) used by terrorist to send key instructions. Anyway, here is a site where you can play with this thing : http://mozaiq.org/