I. What is CryptographyCryptography is a secret technique in which the users involved create a real message but it is hidden in one way or another. One form of cryptography is steganography. This is another secret technique, a little older than cryptography itself. It has been used for thousands of years, but as a primitive form of secret messages. The word itself is a derivative of two Greek words: steganos means “to cover” and graphein means “to write”. In ancient times, a man named Pliny the Elder used the milk of a thitymallus plant as invisible ink. In Greece and Persia, a messenger's head was shaved, a message was written on his bald head, and then hair was waited to grow on it before sending to deliver the message. Sometimes they would go so far as to tattoo the message on his head. Obviously, the message couldn't be extremely urgent. The technique of steganography is not used much for security reasons these days because it has become obscure. It has strengths and weaknesses, one of the major weaknesses being that if the message is found, the secret is exposed. Cryptography is another method used to hide the meaning of a message. Cryptography is also derived from Greek, specifically from the word kryptos, which means “hidden.” Cryptography techniques are different from steganographic techniques in that they do not hide the actual message, only the meaning of the message. If the message fell into the wrong hands, the use of cryptography would ensure that the message could not be read, whereas steganography would not, the message would be read. Usually, a sender and receiver agree on the type of scrambling protocol they would use before attempting to send a message. They would also agree middle of paper...... Key and private keys. "Public keys and private keys. Np, nd Web. March 18, 2014." History of cryptography. " Wikipedia. Wikimedia Foundation, March 15, 2014. Web. March 18, 2014. "Public Key Cryptography for Dummies." Public Key Encryption for Dummies, nd Web, March 18, 2014. "A Brief History of RSS Cryptography. . Np, nd Web. March 17, 2014. “A Brief History of Cryptography.” Thawte Crypto Challenge – Can you be the first to crack the code in our Cryptography Challenge? NSRP: Cryptography. Np, nd Web. March 18, 2014. “Cryptography defined/brief history.” Cryptography defined/brief history. Np, nd Web. March 18, 2014."Private key (secret key)." What is Np, nd Web. March 18, 2014. “Public and Private Key Encryption Systems.” » Np, March 18.. 2014.