Untitled

<html>
<head>
<title> Registration</title>
</head>

<body>

    <form action='login.php' method='POST'>
        Username:   <input type='text' name ='username'><br />
        Password:   <input type='password' name ='password'><br />
        <input type='submit' value ='Log In'>

    </form>
</body>
</html>

//login.php file below
<?php

//$username= $_POST['username'];
//$password= $_POST['password'];

isset($_POST['username']) ? $username = $_POST['username'] : 'You did not enter a Username!';
isset($_POST['password']) ? $password = $_POST['password'] : 'You did not enter a Password!';

// Example usage for: Ternary Operator
$action = (empty($_POST['action'])) ? 'default' : $_POST['action'];

?>