Classic & Modern Cryptographic Ciphers 🔐

A compact collection of classical and modern cryptographic algorithms implemented in Python. This repository is intended for learning, experimentation, and understanding how traditional and widely-used encryption techniques work under the hood.

---

🧠 What’s Included

🔸 Classical Ciphers

These are historic encryption algorithms used before the advent of modern cryptography:

• Caesar Cipher – Simple substitution using character shifts
• Playfair Cipher – Bigram substitution based on a 5x5 key matrix
• Rail Fence Cipher – Zigzag transposition cipher

🔹 Modern Ciphers

These represent the foundational concepts of modern-day encryption:

• RSA Cipher – Asymmetric encryption using large prime numbers
• DES (Data Encryption Standard) – Symmetric key block cipher (now deprecated)
• AES (Advanced Encryption Standard) – Industry-standard secure encryption

---

📁 Repository Structure

Each file contains a standalone implementation with test examples and optional helper functions.

---

⚙️ Requirements

Most algorithms use only standard Python libraries. For AES and DES, you may need:

pip install pycryptodome