ASP.NET Core has many different types of IActionResult:
ViewResult : Generates an HTML view.
RedirectResult : Sends a 302 HTTP redirect response to send a user to a specified URL automatically.
RedirectToRouteResult : Sends a 302 HTTP redirect response to automatically send a user to another page, where the URL is defined using routing.
FileResult : Returns a file as the response.
ContentResult : Returns a provided string as the response.
StatusCodeResult : Sends a raw HTTP status code as the response, optionally with associated response body content.
NotFoundResult : Sends a raw 404 HTTP status code as the response.
