Two-Factor Authentication (2FA) is an extra layer of security used to protect online accounts by requiring two forms of verification before granting access. Instead of just entering a password, users must also provide a second factor, making it much harder for hackers to gain access.
Typically, we say that for two-factor authentication, you need to have 2 of the 3 of the following groups of authentication:
1. Something you know
This is typically a password or phrase
2. Something you have
This is something physical, like a physical security token
3. Something you are
This is typically biometric in nature. Fingerprint, face, and even retina scans.
Using a combination of these groups, systems can help secure resources against bad actors. In addition to the user providing any of the three factors above, the authentication system usually looks at other derived information such as:
Geographical location – Are you trying to login from somewhere that’s familiar to you, or are you away from home (higher risk)
Type of equipment you are logging in from – Are you using a device that’s familiar to the authentication system? Is it a random public device or unknown device (higher risk)
How 2FA Works
When logging into an account with 2FA enabled, you’ll need to:
- Enter your password (something you know).
- Verify your identity using a second factor, such as:
- A one-time code sent to your phone via SMS.
- A code from an authentication app (Google Authenticator, Authy, etc.).
- A biometric scan (fingerprint or facial recognition).
- A hardware security key (YubiKey, Titan Security Key).
Types of 2FA Methods
- SMS or Email Codes – A temporary code sent to your phone or email.
- Authenticator Apps – Apps like Google Authenticator, Authy, or Microsoft Authenticator generate time-sensitive codes.
- Biometric Authentication – Using Face ID, Touch ID, or fingerprint scanning.
- Hardware Security Keys – USB or NFC keys like YubiKey provide physical authentication.
- Backup Codes – A set of pre-generated codes you can use when other methods are unavailable.
Why Use 2FA?
- Enhances Security – Even if your password is stolen, hackers can’t access your account without the second factor.
- Prevents Unauthorized Access – Helps protect against phishing, data breaches, and password leaks.
- Required by Many Services – Google, Apple, Microsoft, and banks recommend or require 2FA.
How to Enable 2FA
- Go to your account security settings (Google, Facebook, etc.).
- Look for “Two-Factor Authentication” or “2-Step Verification.”
- Choose a verification method (SMS, Authenticator app, security key, etc.).
- Follow the setup instructions and save backup codes.
Final Thoughts
2FA is one of the best ways to keep your online accounts secure. For even stronger protection, use an authenticator app or a hardware key instead of SMS codes, as phone numbers can be hacked via SIM swapping.