root@svn ~/php [0.07 0.02]> cat explode.php 
<?

$pizza = "p1 p2 p3";
$pieces = explode(" ",$pizza);
print_r($pieces);
?>
16:07:56
root@svn ~/php [0.07 0.02]> php explode.php 
Array
(
    [0] => p1
    [1] => p2
    [2] => p3
)

root@svn ~/php [0.07 0.02]> cat explode1.php 
<?
$data = "smmsp:x:51:51::/var/spool/mqueue:/sbin/nologin";
list($user,$pass,$uid,$gid,$gecos,$home,$shell) = explode(":",$data);

echo $user.",".$home.",".$shell;
?>
16:10:46
root@svn ~/php [0.07 0.02]> php explode1.php 
smmsp,/var/spool/mqueue,/sbin/nologin