What are the advantages of using sessions over IP addresses for identifying visitors in PHP applications?

Using sessions over IP addresses for identifying visitors in PHP applications provides better security and privacy for users. Sessions are unique identifiers stored on the server side, making it harder for malicious users to manipulate their identity. Additionally, sessions are not tied to a specific IP address, allowing users to access the application from different devices without being logged out.

// Start a session
session_start();

// Set a unique identifier for the user
$_SESSION['user_id'] = uniqid();