How can PHP ensure that passwords are stored securely and account for case sensitivity in password validation processes?

To ensure that passwords are stored securely in PHP, you should always hash the passwords using a secure hashing algorithm like bcrypt. When validating passwords, you can use the password_verify function to compare the hashed password with the user input. To account for case sensitivity in password validation processes, you can either convert both the input password and the stored password to lowercase before hashing and comparing them.

// Hashing the password using bcrypt
$hashed_password = password_hash($password, PASSWORD_BCRYPT);

// Validating the password
if (password_verify($input_password, $hashed_password)) {
    // Password is correct
} else {
    // Password is incorrect
}