Ory Identities is an API-first identity and user management system provided by Ory. It offers secure authentication and user management capabilities for applications at any scale. Ory Identities implements best-practice authentication methods while securing identities, credentials, and sessions. It supports various authentication options including multi-factor authentication, passkeys, social sign-in, and biometric authentication. Ory Identities provides customizable API flows and a theme builder for creating branded login experiences. It integrates with applications through APIs and SDKs, and supports OpenID Connect for connecting first and third-party apps.