How can PHP sessions be effectively utilized to store and maintain variable values across multiple page loads?

To store and maintain variable values across multiple page loads in PHP, you can use sessions. Sessions allow you to store variables that can be accessed across different pages for a specific user during their visit to the website. To utilize PHP sessions effectively, you need to start the session at the beginning of each page where you want to access the stored variables and then use the $_SESSION superglobal array to set and retrieve the values.

<?php
// Start the session
session_start();

// Set a session variable
$_SESSION['username'] = 'JohnDoe';

// Retrieve the session variable
echo $_SESSION['username'];
?>