$str = "PolarBear";
$str =~ /polarbear/; #returns 2, and/or [0,5] for positions
         ^    ^
$str =~ /Polerbear/; #returns 2, and/or [3,5] for positions
            ^ ^
$str =~ /Polarbeer/; #returns 3, and/or [5,7] for positions
              ^ ^