Category: Security

What is symmetric vs asymmetric encryption? One key versus a public/private key pair. Learn how each works, when to use them, and how they combine in TLS.

What is a rainbow table? A precomputed structure that reverses unsalted password hashes using a time-memory tradeoff. Learn how salts defeat it.

What is Argon2? The Password Hashing Competition winner, a memory-hard, salted algorithm. Learn its variants, parameters, and why Argon2id is recommended.

What is bcrypt? A slow, salted password hashing function with a tunable cost factor. Learn its hash format, the 72-byte limit, and how to use it safely.

What is salting a password? Adding a unique random value before hashing so identical passwords hash differently. Learn salts vs pepper and common mistakes.

HMAC combines a hash function with a shared secret key to prove a message is authentic and unaltered. Here is how it works and where you meet it.

A cryptographic hash turns any input into a fixed-size fingerprint that is one-way and collision-resistant. The properties that matter and what they enable.

The alg:none attack tricks a JWT verifier into accepting an unsigned token by trusting the header. Learn how it works and how to shut it down.

Password entropy measures unpredictability in bits. Learn how pool size and length set it, and why it only counts for truly random passwords.

JWTs are stateless and self-contained; session cookies are stateful and server-tracked. Learn the trade-offs in revocation, storage, and size.