$email_a = 'joe@example.com';
$email_b = 'bogus';

if (filter_var($email_a, FILTER_VALIDATE_EMAIL)) {
    echo 'This ('.$email_a.') email is valid.';
}

if (!filter_var($email_b, FILTER_VALIDATE_EMAIL)) {
    echo 'This ('.$email_b.') email is NOT valid.';
}

$ip_a = '127.0.0.1';
$ip_b = '42.42';

if (filter_var($ip_a, FILTER_VALIDATE_IP)) {
    echo 'This ('.ip_a.') IP address is  valid.';
}
if (!filter_var($ip_b, FILTER_VALIDATE_IP)) {
    echo 'This ('.ip_b.') IP address is NOT valid.';
}