Email validation snippet in PHP

$email = $_POST['email'];

if(preg_match("~([a-zA-Z0-9!#$%&'*+-/=?^_`{|}~])@([a-zA-Z0-9-]).([a-zA-Z0-9]{2,4})~",$email)) {

    echo 'This is a valid email.';

} else{

    echo 'This is an invalid email.';

}