perlquestion truthseeker66 <p>I see a line, "@sorted = sort {$a <=> $b} @array;" <br> </p> <p> The text book I read says, "When you need to sort data in <br> numerical order, you have to add an argument to the sort<br> statement. What confuses me is '$a <=> $b'. <br> Could you explain what this line do? Can I use '$c <=> $d'<br> instead? </p> Thank you