What are some best practices for securely handling user authentication and session management in PHP applications?

One best practice for securely handling user authentication and session management in PHP applications is to use secure hashing algorithms like bcrypt to securely store and verify passwords. Additionally, always use HTTPS to encrypt data in transit and prevent man-in-the-middle attacks. Lastly, regenerate session IDs after a user logs in or their privilege level changes to prevent session fixation attacks.

// Example of securely hashing a password using bcrypt
$password = "securepassword123";
$hashed_password = password_hash($password, PASSWORD_BCRYPT);

// Example of verifying a hashed password
if (password_verify($password, $hashed_password)) {
    echo "Password is correct!";
} else {
    echo "Password is incorrect!";
}

// Example of regenerating session ID
session_regenerate_id(true);