I have come across a line of code. I can't seem to understand what it does. I know that it searches for the "&" character in $ENV("QUERY_STRING"). But I can't seem to understand the line of code a bit later asking if $_==4. Can some help explain this, and what this line is looking for? 
$_=split /&/,$ENV{"QUERY_STRING"};
...
...
...
if ($_==4){print "<p>";$pong=`./.blah.pl`;print $pong;}

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In reply to Split Line by Anonymous Monk

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