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#hash
2 articles
01
2026-08-26
·
Security
·
FREE
·
13 min read
Cryptography from Scratch — Symmetric Keys, Public Keys, and Hashes
Cryptography isn't about producing unreadable text — it's about engineering an extreme gap in effort between people who hold the key and people who don't. We build up the three tools (symmetric, public-key, hashing) from zero, explain why factoring shows up at all, what a signature actually promises, and how every widely deployed cipher has eventually broken.
02
2026-08-13
·
Data Structures
·
FREE
·
PAPER
·
9 min read
Hashing and Nearest-Neighbor Search — The Groundwork Under Vector Search
Two inventions that made looking things up fast — the exact-match hash table, and LSH and HNSW for searching by meaning — from zero assumed knowledge. What is actually running underneath RAG and every vector database.