What is the main function of Amazon Cognito?

Amazon Cognito's primary role is to manage and verify user identity by providing user authentication, authorization, and user management services. It supports various sign-in options, including social identity providers such as Google, Facebook, and Amazon, as well as enterprise identity providers via SAML, and custom user pools. This allows developers to easily handle user sign-ups, logins, and password resets while securely managing user sessions.

Through Cognito, applications can ensure that only verified users can access certain resources or services, thus enhancing security and enabling personalized experiences in applications. It also automates the handling of user credentials and session management, reducing the burden on developers to implement these security protocols directly.

The other options present different AWS services or functions. Content delivery over the internet is typically managed by Amazon CloudFront, cloud storage solutions are provided by Amazon S3 or EBS, and improving database performance usually falls under the scope of Amazon RDS or DynamoDB. Each of these serves distinct purposes unrelated to user identity management, reinforcing why managing and verifying user identity is the accurate focus of Amazon Cognito.