PHP program to cancatenate two string

PROGRAM

<?php
echo "
<form method='POST' action='' >
FIRST :<input type='text' name='first'>
SECCND :<input type='text' name='seccond'>

<input type='submit' value='submit' name='submit'>
</form>
";
if(isset($_POST['submit']))
{
$first=$_POST['first'];
$seccond=$_POST['seccond'];
echo "STRING CANCATINATION"."<BR/>";
echo $first.$seccond;
}

?>

OUTPUT