What are some potential pitfalls to avoid when working with PHP sessions, especially in the context of protecting login areas?

One potential pitfall to avoid when working with PHP sessions in protecting login areas is session fixation attacks. To prevent this, you should regenerate the session ID after a successful login to prevent an attacker from fixing the session ID before the user logs in.

// Start the session
session_start();

// Regenerate the session ID
session_regenerate_id(true);