Part one of term paper
is the science of encoding a message into a form that is unreadable and making sure only the proper people are capable of decoding the message back into its original form. This is usually done by using an encryption algorithm and a decryption algorithm (these two are often the same) and very often a secret key. Some of the early cryptographi ...

Part two of term paper
... message is intercepted on the way by a third party, they will only have unreadable data and will have gained nothing, unless they can figure out the decryption algorithm and obtain the key. This is why the key is never to be sent with the message, and has to be kept secret at all cost. If the key is compromised, the sender and the encrypted data is no longer safe. The sender and the receiver then usually agree on a new key to prevent any further damage. In ancient Greece, around 550 Bc, messages w ...