if ($_SERVER['REQUEST_METHOD'] === 'POST') { $username = $_POST['username']; $password = $_POST['password']; // Do something with the submitted values }In this example, we are checking to see if the form has been submitted using the POST method, and if it has, we are retrieving the values of the `username` and `password` fields using the `$_POST` superglobal. The PHP Request postParam method is part of the PHP HTTP Request library. This library provides a set of classes and functions for working with HTTP requests, including methods for handling POST requests. Some popular HTTP Request packages for PHP include Guzzle, Requests, and Buzz.