Error.prototype.name: Error Error.prototype.message: Error.prototype.toString(): [object Error] noMessage.name: Error noMessage.message: noMessage.toString(): [object Error] withMessage.name: Error withMessage.message: I have a message for you... withMessage.toString(): [object Error] Changing Error.prototype.name to TryNewName... Error.prototype.name: TryNewName withMessage.name: TryNewName Message: Range Error's prototype