What are the best practices for handling data transport between page reloads in PHP?

When handling data transport between page reloads in PHP, it is best practice to use sessions to store and retrieve data. Sessions allow you to persist data across multiple page loads for a specific user. By storing data in sessions, you can easily access it on subsequent page reloads without the need to pass data through URLs or forms.

// Start or resume a session
session_start();

// Store data in session
$_SESSION['data'] = 'Hello, world!';

// Retrieve data from session
$data = $_SESSION['data'];

// Unset data from session if no longer needed
unset($_SESSION['data']);