Path to the 'app' folder

<?php
/**
 * Path to the 'app' folder
 */
echo app_path();
/**
 * Path to the project's root folder
 */
echo base_path();
/**
 * Path to the 'public' folder
 */
echo public_path();
/**
 * Path to the 'app/storage' folder
 */
echo storage_path();
?>