In what scenarios would using a session be recommended for passing data between PHP scripts?

Using a session in PHP is recommended for passing data between scripts when you need to store information that needs to persist across multiple requests. This is useful for scenarios where you want to maintain user login information, shopping cart contents, or any other data that needs to be accessed throughout a user's session on the website.

// Start a session
session_start();

// Store data in the session
$_SESSION['user_id'] = 123;
$_SESSION['username'] = 'john_doe';

// Retrieve data from the session in another script
session_start();
$user_id = $_SESSION['user_id'];
$username = $_SESSION['username'];

// Use the data as needed
echo "User ID: $user_id, Username: $username";