• An Amazon Cognito user pool is a user directory for web and mobile app authentication and authorization.
• From the perspective of your app, an Amazon Cognito user pool is an OpenID Connect (OIDC) identity provider (IdP).
• A user pool adds layers of features for security, identity federation, app integration, and user experience customization.
  • You can, for example, verify that your users’ sessions are from trusted sources.
  • You can combine the Amazon Cognito directory with an external identity provider.
• With your preferred AWS SDK, you can choose the best API authorization model for your app.
• You can add AWS Lambda functions that modify or overhaul the default behavior of Amazon Cognito.