What is Authentication?

1 min read Updated 2026-02-05

The process of verifying the identity of a user, device, or system. Common methods include passwords, multi-factor authentication (MFA), and OAuth.

Related: Authorization MFA OAuth Session Management

Understanding Authentication

Authentication answers the question "Who are you?" It's the first line of defense in securing an application. Weak authentication mechanisms are one of the most common causes of security breaches, allowing attackers to impersonate legitimate users.

Examples

  • Username and password login forms
  • OAuth login with Google or GitHub
  • Biometric authentication (fingerprint, face recognition)
  • Hardware security keys (YubiKey)

How to Prevent

  • Implement multi-factor authentication (MFA)
  • Use secure password hashing (bcrypt, Argon2)
  • Enforce strong password policies
  • Implement account lockout after failed attempts
  • Use secure session management

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