What is meant by the HTTP 404 status in web applications?

HTTP status 404 means that the requested resource was not found on the server. It is a standard server response indicating to the client that there is no page or file at the specified URL. For example, if a user tries to open a page that has been deleted or never existed, the server will return 404.

This is important for web applications to correctly inform the user about the unavailability of the resource and, if necessary, display a user-friendly error page.