In that instance, $_ could be anything. But you can assign directly to $_ to let m// use it as default instead. 
$_= "Best winkles in Sunderland";

if (/under/) {
    print "We're talking about rugby\n";
}

[download]
The more common use of $_ is when it's the default iterator in a for loop, or in a while loop when reading from a file. 
# Instead of having for my $iter, for uses $_ as the iterator below:
for ("Up and under", "Best winkles in Sunderland") {
    if (/under/) {
        print "We're talking about rugby\n";
    }
}

[download]

In reply to Re: The $_ Special Variable by wind
in thread The $_ Special Variable by chuloon

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