Alice and Bob have secrets they want to talk about without Eve being able to listen in. Worse yet, the mischievous Mallory delights in changing messages sent between parties. In such a hostile environment how can Alice talk to Bob without their messages being overheard and how can she be sure that it was Bob that sent the message in the first place? This talk will take a brief look at historic codes and ciphers before taking a look at modern day Cryptography. If you want to be able to know the difference between a block cipher and a stream cipher or get a glimpse into the mathematics behind public key Cryptography this talk is for you.