strings

<?php
    $s="Faisal";
   echo strlen("Hello world")."<br>";
   echo strpos("Hello world!","world")."<br>";
   echo("Hello world"." ".$s);
   $a = strlen("Faisal");
   $b = strlen("Ahmed");
   if($a== $b)
   {
       echo ("<br>Same length $a");
   }
   else{
       echo ("<br>Length did not match $b");
   }
?>