Cryptography Blog

Explore the world of cryptography through in-depth tutorials, historical analysis, cipher comparisons, and modern encryption concepts.

Security Fundamentals26 min read

MD5 vs SHA-256: Hash Security Comparison Guide

Compare MD5 and SHA-256 hash functions by digest size, collision resistance, speed, file checksums, password risks, and safe use cases.

Hommer Zhao
Security Fundamentals27 min read

AES vs DES: Which Encryption Is Better Today?

Compare AES and DES encryption, including security, key size, speed, history, and why AES replaced DES for modern data protection.

Hommer Zhao
Security Fundamentals25 min read

Symmetric vs Asymmetric Encryption Explained Clearly

Learn how symmetric and asymmetric encryption differ, when each fits, and why modern security systems combine both approaches in real protocols.

Hommer Zhao
Cipher Comparisons24 min read

Substitution vs Transposition Ciphers: Key Differences

Compare substitution and transposition ciphers by rules, examples, attacks, strengths, and teaching value for classical cryptography practice.

Hommer Zhao
Cipher Comparisons22 min read

Caesar Cipher vs Atbash Cipher: Key Differences

Compare Caesar and Atbash ciphers by key, mapping, history, security, and use cases so you know which tool fits your puzzle or lesson.

Hommer Zhao
Cryptography History18 min read

Arab Scholars and the Invention of Cryptanalysis

Discover how Arab scholars invented frequency analysis and turned cipher solving from educated guesswork into cryptanalytic science.

Hommer Zhao
Cryptography History26 min read

Zimmermann Telegram Cipher That Changed History

Learn how Room 40 decoded the Zimmermann Telegram, exposed Germany's Mexico plan, and helped push the United States into World War I.

Hommer Zhao
Cryptography History27 min read

Purple Machine Japanese Cipher: WWII Cryptanalysis

Learn how Japan's Purple machine worked, how U.S. cryptanalysts broke it, and why MAGIC intelligence shaped WWII diplomacy and Pearl Harbor.

Hommer Zhao
Cryptography History24 min read

Thomas Jefferson Wheel Cipher Invention Explained

Jefferson sketched a 36-disk wheel cipher in the 1790s. See how it worked, why it mattered, and where its security lessons still apply.

Hommer Zhao
Cryptography History27 min read

Mary Queen of Scots Cipher That Led to Execution

How Mary Queen of Scots used a nomenclator cipher in the Babington Plot, how it was broken, and why the evidence led to her execution.

Hommer Zhao
Cryptography History24 min read

Ancient Hebrew Ciphers in the Dead Sea Scrolls

Explore ancient Hebrew ciphers in the Dead Sea Scrolls, from Atbash and cryptic scripts to Qumran secrecy, scribal practice, and modern lessons.

Hommer Zhao
Cryptography History25 min read

Alan Turing's Cryptography Contributions Explained

Explore Alan Turing's cryptography contributions, from Bombe logic and Banburismus to secure speech, computation, and modern lessons.

Hommer Zhao
Cryptography History24 min read

Navajo Code Talkers: WWII's Unbreakable Code System

Explore how Navajo Code Talkers built a fast, layered voice code in World War II, why Japan never broke it, and what cryptography can learn.

Hommer Zhao
Cryptography History23 min read

How the Enigma Machine Worked and Was Broken in WWII

Learn how the Enigma machine's rotors, plugboard, and procedures encrypted wartime traffic, and how Allied cryptanalysts systematically broke it.

Hommer Zhao
Cryptography History20 min read

History of Cryptography: From Ancient Egypt to AES

Trace cryptography history from ancient Egyptian scribes to AES, and see how ciphers, codebreaking, and standards shaped modern security.

Hommer Zhao
Cryptanalysis22 min read

Two-Time Pad Attacks: Why Key Reuse Breaks OTP

Learn how two-time pad attacks exploit reused keys, expose plaintext relationships, and reveal why one-time pad discipline matters in modern cryptography.

Hommer Zhao
Security Fundamentals21 min read

One-Time Pad Perfect Secrecy Explained Clearly

Understand why the one-time pad is theoretically unbreakable, what perfect secrecy really means, and why key reuse destroys it in practice.

Hommer Zhao
Cipher Tutorials20 min read

Columnar Transposition Cipher Guide With Worked Examples

Learn how columnar transposition cipher encryption and decryption work, how keywords set column order, and how to avoid decoding mistakes.

Hommer Zhao
Cipher Tutorials19 min read

Rail Fence Cipher Encoding and Decoding Explained

Learn how rail fence cipher encoding and decoding work, how rail count changes output, and how to fix zigzag transposition errors fast.

Hommer Zhao
Cipher Comparisons18 min read

Beaufort Cipher vs Vigenere: Key Differences Explained

Beaufort and Vigenere look alike, but one reciprocal formula changes encryption, decryption, error checking, and cryptanalysis by hand.

Hommer Zhao
Cipher Tutorials22 min read

Hill Cipher Key Matrix Rules and Inverse Explained

Understand Hill cipher key matrices, determinant checks, modular inverses, and how to avoid invalid keys when encrypting or decrypting text.

Hommer Zhao
Cipher Tutorials21 min read

Hill Cipher Tutorial With Matrix Examples and Tips

Learn how the Hill cipher uses modular matrix math, work through encryption and decryption examples, and understand its strengths and limits.

Hommer Zhao
Cipher Tutorials19 min read

Playfair Cipher Tutorial With Worked Examples

Learn how the Playfair cipher works with grid setup, encryption rules, worked examples, common mistakes, and practical cryptanalysis tips.

Hommer Zhao
Cipher Basics20 min read

ROT13 Explained: Why This Simple Cipher Still Survives

Learn how ROT13 works, why it is not secure, and why this reversible Caesar variant still appears in forums, code jokes, and spoiler hiding.

Hommer Zhao
Cryptography History18 min read

Atbash Cipher in the Bible: Complete Analysis Guide

Explore where the Atbash cipher appears in the Bible, how scholars decode names like Sheshach, and what it reveals about Hebrew cryptography.

Hommer Zhao
Cryptanalysis19 min read

How to Decode Vigenere Cipher Without the Key

Learn how to decode a Vigenere cipher without the key using Kasiski examination, frequency analysis, and practical step-by-step methods.

Hommer Zhao
Cipher Tutorials16 min read

How to Use Caesar Cipher Step by Step: Complete Guide with Examples

Learn how to use the Caesar cipher step by step with clear examples, a comparison table, common mistakes to avoid, and practice workflows for encoding and.

Hommer Zhao