> For the complete documentation index, see [llms.txt](https://book.jorianwoltjer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.jorianwoltjer.com/cryptography.md).

# Cryptography

- [Encodings](https://book.jorianwoltjer.com/cryptography/encodings.md)
- [Ciphers](https://book.jorianwoltjer.com/cryptography/ciphers.md): Ways to encrypt text. Often methods used a long time ago to send secret messages
- [AES](https://book.jorianwoltjer.com/cryptography/aes.md): The Advanced Encryption Standard is a common symmetric encryption standard with a few different modes of operation
- [Asymmetric Encryption](https://book.jorianwoltjer.com/cryptography/asymmetric-encryption.md): Using Public and Private keys to securely transmit data in a way that only the recipients can decrypt it
- [RSA](https://book.jorianwoltjer.com/cryptography/asymmetric-encryption/rsa.md): An encryption standard using prime number factorization to encrypt and decrypt with an asymmetric keypair
- [Diffie-Hellman](https://book.jorianwoltjer.com/cryptography/asymmetric-encryption/diffie-hellman.md): The Diffie-Hellman Key Exchange uses asymmetric encryption to set up a shared secret for symmetric encryption
- [PGP / GPG](https://book.jorianwoltjer.com/cryptography/asymmetric-encryption/pgp-gpg.md): The "Pretty Good Privacy" asymmetric encryption scheme used in email and sending encrypted or signed messages
- [Pseudo-Random Number Generators (PRNG)](https://book.jorianwoltjer.com/cryptography/pseudo-random-number-generators-prng.md): Often the default random function in whatever language is not cryptographically secure, making it possible to predict values
- [Hashing](https://book.jorianwoltjer.com/cryptography/hashing.md): One-way functions that generate a unique hash of some data
- [Cracking Hashes](https://book.jorianwoltjer.com/cryptography/hashing/cracking-hashes.md): The point of hashes are that you can't reverse them, but we can sometimes find the original text by brute-forcing
- [Cracking Signatures](https://book.jorianwoltjer.com/cryptography/hashing/cracking-signatures.md): Some examples of signature implementations (often HMAC) that can be cracked using hashcat
- [XOR](https://book.jorianwoltjer.com/cryptography/xor.md): An operation between bits used often in cryptography
- [Custom Ciphers](https://book.jorianwoltjer.com/cryptography/custom-ciphers.md): "Never roll your own crypto" is a saying for a reason. It's hard to make a secure cryptographic algorithm because there are many ways it may be broken
- [Z3 Solver](https://book.jorianwoltjer.com/cryptography/custom-ciphers/z3-solver.md): The Z3 Theorem Prover can automatically solve puzzles in Python
- [Timing Attacks](https://book.jorianwoltjer.com/cryptography/timing-attacks.md): Using timing information to extract information
- [Blockchain](https://book.jorianwoltjer.com/cryptography/blockchain.md)
- [Smart Contracts](https://book.jorianwoltjer.com/cryptography/blockchain/smart-contracts.md): A few small bits about attacking Smart Contracts in Web3
- [Bitcoin addresses](https://book.jorianwoltjer.com/cryptography/blockchain/bitcoin-addresses.md): A bit of information about Bitcoin addresses