# Authentication

> How a Shoplazza App authorizes with OAuth 2.0: the authorization code flow, the access scopes it can request, and HMAC request signature verification.

Shoplazza uses OAuth 2.0 to authorize third-party apps. This section covers the authorization flow, access scopes, and request signature verification.

- [OAuth flow](/docs/app/building-blocks/authentication/oauth-flow): Understand the authorization code grant flow
- [Access scopes](/docs/app/building-blocks/authentication/access-scopes): Learn about available permission scopes
- [Signature verification](/docs/app/building-blocks/authentication/signature-verification): Verify request authenticity