Forge Capsule

Cryptographic Hash Functions: SHA-256, Keccak, and BLAKE3

Hash function properties: pre-image resistance, second pre-image resistance, collision resistance. SHA-2: Merkle-Damgård construction, SHA-256 (256-bit output, 64 rounds). SHA-3/Keccak: sponge construction, rate+capacity, lane operations. BLAKE3: Merkle tree structure, parallel, 128-bit security, faster than MD5 on modern hardware. HMAC: keyed hash for MACs. Password hashing: Argon2id (memory-hard, recommended), bcrypt, scrypt. Merkle trees: hash trees for efficient verification — Bitcoin, Ethereum, Forge provenance chains. Git: SHA-1 (legacy), SHA-256 (new). Forge ZK: Poseidon hash (ZK-friendly, BN254 field).