cryptography: why, how, and who to thrust (+ keysigning party)

Computer security day is around the corner so we decided to give a talk about cryptography.
Things we will cover

*Why do we need cryptography
*Brief overview of cryptography trough the ages
*Cryptography today, how does it work
*Private key encryption, a brief look at the math behind it.
*Why HTTPS should (not) always be thrusted
*hands on PGP / GPG (bring your computer!)
*Key signing party

No prior knowledge required.