- print_r: documentation ( source)
- array_merge: documentation ( source)
<?php
$array1 = array(
1 => array('stuff'),
2 => array('stuff'),
);
$array2 = array(
1 => array('other stuff'),
3 => array('other stuff'),
);
print_r(array_merge($array1, $array2));
print_r($array1 + $array2);