Learn essential concepts of cryptography as it is used on the modern Internet, including hashing, symmetric encryption, and asymmetric encryption. Then perform hands-on projects calculating hashes and encrypting secrets with RSA and AES, and compete to solve challenges including cracking Windows and Linux password hashes, short and poorly-chosen RSA public keys, and poorly-chosen AES keys. We will also cover Blockchains, the technology behind Bitcoin. No previous programming experience required. Students need to bring a computer that can run Python; any version of Mac, Windows, or Linux will be fine. I will have a few loaner computers for students who don't have a usable computer. All materials, projects, and challenges are freely available at https://samsclass.info/124/Defcon-BSidesLV-2016-crypto.shtml