In what situations would using require instead of include be more appropriate for accessing variables in PHP?

Using require instead of include would be more appropriate when accessing variables in PHP if you want to make sure that the file being included is essential for the script to run properly. If the included file contains essential functions or variable definitions that are crucial for the script's functionality, using require ensures that the script will halt with a fatal error if the included file is not found or cannot be included. This can help prevent unexpected behavior or errors in your PHP script.

require 'config.php';
// Code that relies on variables or functions from config.php