When is the HTTP PUT method used?

The HTTP PUT method is used to create or replace a resource on a server. While not its primary or most common use, some DNS server APIs (Application Programming Interfaces) might utilize HTTP PUT to update DNS records. This involves sending the complete updated record to the server, replacing any existing record at that specific URI. "When a nonidempotent operation is needed" is incorrect because PUT is an idempotent method. Idempotent means that multiple identical requests will have the same effect as a single request. "To display a web site" is incorrect; displaying a website typically uses the HTTP GET method. "When a read-only operation is required" is also incorrect; read-only operations use GET.