Since ancient times, individuals have been working to devise manners through which communications could be made private. Julius Caesar employed a secret code in which the original messages letters were replaced with the alphabets letter three spaces to the right. During World War II, cryptography allowed the Allied forces to learn when Japan intended to attack Midway Island and thus prepare for the attack and emerge victorious. Unfortunately, todays cell phone traffic has only a small percentage of calls that are encrypted. Encryption is the process that converts the ordinary language, or plaintext, into ciphertext--or gibberish that cannot be easily deciphered without a key. The goal of such a system would be to provide security and comfort to authorized users that possess the encryption key, at the same time making the information extremely difficult to comprehend without the key. There are two types of cryptography employed today--private-key and public-key cryptography. Private-key cryptography is often more expensive and the biggest setback is key management. In these instances, the keys need to be changed often. When it comes to public-key cryptography, there are a private key and a public key in use. For the most part, the public key is used to encrypt information while the private key is used to decrypt information. Public-key cryptography is used commonly on the Internet when individuals are surfing the Web.