Php @

Can someone tell me what this symbols means in php: @. I have been searching and cannot find the answer. Maybe also if you could point me to a tutorial or documentation that deals with that. here is the code that I am looking at that has it there


<?php
if (@include(getenv('DOCUMENT_ROOT').'/adserver/phpadsnew.inc.php')) {
if (!isset($phpAds_context)) $phpAds_context = array();
$phpAds_raw = view_raw ('zone:4', 0, '', '', '0', $phpAds_context);
echo $phpAds_raw['html'];
}
?>

it supresses any errors a function may output. For example, try the below.


<?php
mysql_connect("falsehost","fake","details");
@mysql_connect("falsehost","fake","details");
@mysql_connect("falsehost","fake","details") or die ("custom error");
?>

Maybe also if you could point me to a tutorial or documentation that deals with that.
http://www.php.net/operators.errorcontrol