Python Cryptography: Building and Hacking Classical Ciphers

Understanding how data is secured starts with the fundamentals of encryption. Exploring historical ciphers is the perfect way to build a strong foundation in cryptographic concepts while sharpening your programming skills.\n\nIn this text-based course, you will transition from a curious beginner to confidently writing, analyzing, and decrypting classical ciphers. You will read clear explanations, study structured code examples, and practice implementing algorithms that shaped the history of secret communication.\n\nWhat you'll learn:\n- Understand core cryptographic concepts like plaintext, ciphertext, keys, substitution, and transposition.\n- Build classic encryption algorithms including the Caesar, ROT13, and Vigen\u00e8re ciphers from scratch in Python.\n- Apply modern Python practices such as type hints and clean string manipulation to ensure robust code.\n- Analyze cipher vulnerabilities and write scripts to crack encrypted messages using frequency analysis and brute-force methods.\n- Practice writing basic unit tests with pytest to verify the reliability of your encryption and decryption functions.\n\nThe course starts with essential terminology and the mathematical principles of early cryptography. You will then progress through step-by-step written guides to construct, test, and safely break various historical ciphers.\n\nThis course is designed for beginner programmers and security enthusiasts who want a hands-on introduction to cryptography. No prior knowledge of security or advanced mathematics is required; basic Python familiarity is helpful.\n\nStart your journey into the world of secure coding and classical cryptography today.