gistfile1.php

<?php
$now = microtime(true);
for($i = 0; $i < 1000000; $i++){
	$str = 2 + 'characters';
}
echo microtime(true) - $now;
$now = microtime(true);
for($i = 0; $i < 1000000; $i++){
	$str = 2 . 'characters';
}
echo ' as compared to ';
echo microtime(true) - $now;