How does the session ID function in PHP contribute to session security?

Session IDs in PHP contribute to session security by providing a unique identifier for each user's session. This helps prevent session hijacking and session fixation attacks, as each session ID is generated randomly and is difficult to predict. By using session IDs, PHP can track and authenticate users without exposing sensitive information in URLs or cookies.

// Start the session
session_start();

// Regenerate session ID to prevent session fixation
session_regenerate_id(true);