ASP.NET Core Identity is a fully featured membership system for creating and maintaining user logins. Using Identity API, you can sign in & sign out users, reset their passwords , lockout users & Implement Multi Factor Authentication. It can also integrate with the external login providers like Microsoft Account, Facebook, Google, etc.
When we create a new application, we can install the ASP.NET Core identity by choosing the Individual Accounts under the Authentication Type Option. Most of the Identity related services and UI forms like Register, Login & Logout are automatically created for us.