🔑 Authentication Explained Like You're 5

Proving you are who you claim to be Day 95 of 149 👉 Full deep-dive with code examples The Bouncer Analogy A club bouncer checks your ID: You claim to be Alice You show ID proving you're Alice Bouncer lets you in Authentication verifies identity. Authentication Factors Factor Type Example Something you know Knowledge Password, PIN Something you have Possession Phone, YubiKey Something you are Biometrics Fingerprint, face Multi-Factor Authentication (MFA) Combining factors = much stronger: Step 1: Enter password (know) Step 2: Enter code from phone (have) Even if attacker knows password, they don't have your phone! Common Methods Method How It Works Password Check against stored hash OAuth/OIDC "Continue with Google" style sign-in Magic Link Email with login link Biometrics Fingerprint/face scan Hardware Key Physical USB device Authentication vs Authorization Authentication (AuthN) Authorization (AuthZ) WHO are you? WHAT can you do? Verifies identity Grants permissions Login Admin vs use