Introduction to Cryptography: Basics and Techniques

This lecture covers the basics of cryptography, including the one-time pad, perfect secrecy, and public-key cryptography. It explains the importance of privacy and authenticity in communication, the historical context of cryptography, and various encryption techniques. The instructor discusses the fundamental concepts of plaintext, ciphertext, keys, encryption, and decryption. The lecture also delves into ancient ciphers like Caesar's cipher, monoalphabetic ciphers, and polyalphabetic ciphers. It explores the concept of perfect secrecy and the vulnerabilities of different cryptosystems. The one-time pad is highlighted as a secure encryption method, emphasizing the significance of high-entropy keys for achieving perfect secrecy.