Authentication
Authentication is the process of verifying a user's identity, confirming that someone is who they claim to be before granting access to a system, application, or resource.
Authentication is the gatekeeper of every secure application. It answers the question "who are you?" (as opposed to authorization, which answers "what are you allowed to do?"). Common authentication methods include passwords, social logins (Sign in with Google/Apple), multi-factor authentication (MFA), magic links, biometrics, and API keys.
When a user logs in, the server issues a token (usually a JWT, JSON Web Token) that the client includes with subsequent requests. This approach is stateless, scalable, and works well across different platforms and devices. OAuth 2.0 and OpenID Connect are the standard protocols for authentication in modern applications.
In practice
- A SaaS platform added 'Sign in with Google' alongside email/password and saw new user signups increase by 25% because it reduced friction
- An online banking application implemented multi-factor authentication, reducing account takeover incidents by 99%
- A healthcare portal switched from custom-built auth to Auth0, passing their HIPAA security audit in half the time previously required
- An e-commerce site implemented passwordless magic link authentication, reducing abandoned signups by 15% and support tickets about forgotten passwords by 40%
More in Web development
- Responsive Design
- Progressive Web App (PWA)
- Single-Page Application (SPA)
- Server-Side Rendering (SSR)
- Static Site Generation (SSG)
- API (Application Programming Interface)
- CMS (Content Management System)
- Headless CMS
- Version Control
- CI/CD (Continuous Integration / Continuous Deployment)
- JavaScript Framework
- TypeScript
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