LESSON 3

Authentication

Learning objective: Understand how systems verify who you are.

Understand

Authentication proves your identity to a system.

Authentication uses factors: something you know (password), something you have (a phone or key), and something you are (fingerprint). Combining factors — multi-factor authentication (MFA) — is far stronger than a password alone.

Analogy: MFA is like needing both a key and a code to open a safe.

See It in Action

The three authentication factors:

Know - password / PIN
Have - phone code / security key
Are  - fingerprint / face
How it works: Using two different factors together makes stolen passwords far less useful to attackers.

Try It Yourself

  1. Turn on MFA for one important account.
  2. Identify which factors it uses.
  3. List an account that still needs MFA.

Quick Quiz

What makes MFA stronger than a password alone?

Challenge

Enable MFA on an account and note which factors it combines.

Success condition: One of your accounts is protected by multi-factor authentication.