This is a simple random password example , you could generate this for a visitor to use and store it in a database.

<?php
function random_password ()
{
$seed = (integer) md5(microtime());
mt_srand($seed);
$password = mt_rand(1,99999999);
$password = substr(md5($password), mt_rand(0, 19), mt_rand(6, 12));
return $password;
}
?>
<?php
$msg = random_password();
echo $msg;
?>

In action (refresh to change the password)

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