How can PHP developers ensure that their code is more efficient and maintainable when working with session variables?

PHP developers can ensure their code is more efficient and maintainable when working with session variables by minimizing the number of session variables used, avoiding storing large amounts of data in session variables, and properly cleaning up session variables when they are no longer needed.

// Start the session
session_start();

// Set session variables
$_SESSION['username'] = 'JohnDoe';
$_SESSION['email'] = 'johndoe@example.com';

// Unset session variables when they are no longer needed
unset($_SESSION['email']);

// Destroy the session when it is no longer needed
session_destroy();