How can one ensure that session variables are properly unset and reset in PHP to avoid unexpected behavior?

When unsetting and resetting session variables in PHP, it is important to follow the proper steps to avoid unexpected behavior. To ensure that session variables are properly unset and reset, you should first call session_start() at the beginning of the script, unset the specific session variable using unset($_SESSION['variable_name']), and then call session_unset() to clear all session variables. Finally, call session_destroy() to destroy the session completely.

<?php
session_start();

// Unset specific session variable
unset($_SESSION['variable_name']);

// Clear all session variables
session_unset();

// Destroy the session
session_destroy();
?>