gistfile1.aw

<?php
function foo($ob)
{
   ++$ob;
}

$bar=0;

foo($bar);
echo $bar; //echoes 0

foo(&$bar);
echo $bar; //echoes 1


//strings
$string='hello world';

echo "$string"; //echoes 'hello world'
echo '$string'; //echoes '$string'
?>