Symmetric vs. asymmetric, AES vs. Salsa, ECC vs. RSA, Nonce vs. IV, DSA vs. ECDSA vs. EdDSA - it’s easy to get lost in the world of cryptography. This talk discusses the core concepts needed to understand how cryptography is used today. This fast paced talk covers block ciphers and their modes, stream ciphers, the basics of RSA and ECC, hashing, data authentication, and signing; also included are some common issues to avoid - unsafe block modes, fragile primitives, side channels, and other common mistakes.