search Introduction This is the summary of my notes on cryptography I. Overview 1. Symmetry Cryptography Data Encryption Standard Data Encryption Algorithm Advanced Encryption Standard Basic Number Theory -- Euclidean Algorithm Basic Number Theory -- Galois Field Advanced Encryption Algorithm Operation Mode of Block Cipher Operation Mode of Block Cipher Cipher Block Chaining Mode Cipher FeedBack Mode Output FeedBack Mode Counter Mode Random Number Generator Pseudo-random Number Generator Revest Cipher 4 Algorithm